ADDITIONAL CENTER TANK TRANSFER SYSTEM - DESCRIPTION AND OPERATION

** ON A/C NOT FOR ALL

1. General
The additional center-tank transfer-system controls the fuel transfer from the Additional Center Tank (ACT) to the center tank. The ACT is installed in the aft cargo-compartment and can hold approximately 2992 liter (2277 kg) of useable fuel. A fuel line connects the ACT with the main fuel gallery and with the center tank. In flight, an electrical control circuit automatically controls the fuel transfer from the ACT to the center tank via the level sensors in the ACT and center tank. Air pressure from the cabin pressure control system pressurizes the ACT for the forward fuel transfer to the center tank.

A manual selected pump, which is installed in the center tank, provides standby transfer at low flight levels and a transfer capability on the ground. It also transfers fuel during Auto TFR failure.

The refuel transfer system refuels the ACT (Ref. AMM D/O 28-25-00-00).

The aircraft has provisions which lets the operator install and operate the aircraft with one or two Additional Center Tanks. The additional center-tank transfer-system controls the fuel transfer from the Additional Center Tanks (ACT1 and ACT2) to the center tank. The ACTs are installed in the aft cargo-compartment and each ACT can hold approximately 2992 liter (2277 kg) of usable fuel. A fuel line connects the ACT1 and ACT2 with the refuel gallery and the center tank. In flight, an electrical control circuit automatically controls the fuel transfer from the ACT1 and ACT2 to the center tank via the level sensors in the ACT and center tank. Air pressure from the cabin pressure control system pressurizes the ACT1 and ACT2 for the forward fuel transfer.

A manually selected pump, which is installed in the center tank, provides a standby transfer and a transfer capability on the ground. It also transfers fuel during Auto TFR failure

The refuel transfer system refuels each ACT (Ref. AMM D/O 28-25-00-00).

NOTE: For the New Engine Option (NEO) aircraft that has an Additional Center Tank (ACT) installed in the forward cargo compartment, the term ACT FWD can also be written as ACT 4.1.

The aircraft has provisions which let the operator install and operate the aircraft with three ACT(s). The ACT transfer system controls the fuel transfer from the ACT(s) to the center tank. The ACT FWD can be installed in the forward cargo compartment. ACT AFT1 and the ACT AFT2 can be installed in the aft cargo compartment. Each installed ACT can hold 2497 kg (5505 lb) of usable fuel.

A fuel line connects the ACT with the main fuel gallery and with the center tank. In flight, an electrical control circuit, together with the Auxiliary Fuel Management Computer (AFMC) TSM 28460003, automatically controls the fuel transfer from the installed ACT(s) to the center tank. It uses the recorded fuel quantity, which is available in the installed ACT(s) and in the center tank. Air pressure from the cabin pressure control-system pressurizes the ACT(s) to start the fuel transfer from the ACT(s) to the center tank.

The refuel system refuels all the ACT(s) (Ref. AMM D/O 28-25-00-00).

The aircraft has provisions which let the operator to install and operate the aircraft with two ACT(s). The ACT transfer system controls the fuel transfer from the ACT(s) to the center tank. ACT AFT1 and ACT AFT2 can be installed in the aft cargo compartment. Each installed ACT can hold 2497 kg (5505 lb) of usable fuel.
A fuel line connects the ACT with the main fuel gallery and with the center tank. In flight, an electrical control circuit, together with the Auxiliary Fuel Management Computer (AFMC) TSM 28460003, automatically controls the fuel transfer from the installed ACT(s) to the center tank. It uses the recorded fuel quantity, which is available in the installed ACT(s) and in the center tank. Air pressure from the cabin pressure control-system pressurizes the ACT(s) to start the fuel transfer from the ACT(s) to the center tank.
The refuel system refuels all the ACT(s) (Ref. AMM D/O 28-25-00-00).
The Electronic Centralized Aircraft Monitoring (ECAM) gives information about the ACT transfer system to the crew. If specific failures occur:

a fault caption on the AUTO/MAN p/bsw illuminates
a warning is given on the upper ECAM display unit
the fuel page shows on the lower ECAM display unit.

When necessary the crew can make a selection on the ECAM control panel (Ref. 31-56-00) to look at the fuel page.
The Electronic Centralized Aircraft Monitoring (ECAM) and the Auxiliary Fuel Management Computer (AFMC) gives information about the ACT transfer system to the crew. If specified failures occur:

A fault caption on the AUTO/MAN P/BSW comes on
A warning on the upper ECAM display unit comes on
The "FUEL" page on the lower ECAM display unit comes on.

If necessary, the crew can make a selection on the ECAM control panel (Ref. AMM D/O 31-56-00-00) to look at the "FUEL" page.

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2. Component Location

Cockpit - Component Location ** ON A/C NOT FOR ALL

ACT Transfer System - Component Location ** ON A/C NOT FOR ALL

Cockpit - Component Location ** ON A/C NOT FOR ALL

ACT Transfer System - Component Location ** ON A/C NOT FOR ALL

Cockpit Overhead Fuel Panel ** ON A/C NOT FOR ALL

ACT Location - FWD Cargo Compartment ** ON A/C NOT FOR ALL

ACT Location - AFT Cargo Compartment ** ON A/C NOT FOR ALL

Cockpit Overhead Fuel Panel ** ON A/C NOT FOR ALL

ACT Location - AFT Cargo Compartment ** ON A/C NOT FOR ALL

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3. Component Location

FIN	FUNCTIONAL DESIGNATION	PANEL	ZONE	ATA REF
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1QH	PUMP-FUEL TRANSFER, ACT		147	28-28-51
2QH	PRESSURE SWITCH-FUEL TRANSFER PUMP, ACT		147	28-28-00
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3QH	ACTUATOR-AIR SHUTOFF VALVE, ACT	826AR	152	28-28-56
4QH1	ACTUATOR-VENT VALVE, ACT1		150	28-28-00
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4QH2	ACTUATOR-VENT VALVE, ACT2		150	28-28-00
** ON A/C NOT FOR ALL
5QH1	ACTUATOR-FUEL INLET VALVE, ACT1	826AR	150	28-28-00
** ON A/C NOT FOR ALL
5QH2	ACTUATOR-FUEL INLET VALVE, ACT2	826AR	150	28-28-00
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6QH	ACTUATOR-FUEL TRANSFER VALVE, ACT		147	28-28-53
41QU	VALVE-REFUEL, ACT		152	28-25-51
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90QH	ACTUATOR-AIR SHUT OFF VALVE, ACT		152	28-28-00
91QH	ACTUATOR-VENT VALVE, ACT		152	28-28-72
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92QH	ACTUATOR-ISOLATION VALVE, FWD ACT		151	28-28-71
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94QH1	ACTUATOR-FUEL INLET VALVE, ACT1		151	28-28-00
94QH2	ACTUATOR-FUEL INLET VALVE, ACT2		151	28-28-00
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163QM	MOUNTING PLATE-FUEL TRANSFER PUMP, ACT	148AZ	141	28-28-31
165QM	VALVE-FUEL TRANSFER, ACT	148AZ	152	28-28-33
166QM1	VALVE-FUEL INLET, ACT1	826AR	150	28-10-00
167QM1	VALVE-VENT, ACT1	826AR	150	28-10-00
168QM	VALVE-AIR SHUTOFF, ACT	826AR	152	28-28-36
169QM	VALVE-THERMAL RELIEF, ACT TRANSFER	148AZ	141	28-28-46
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163QM	MOUNTING PLATE-FUEL TRANSFER PUMP, ACT		141	28-28-31
165QM	VALVE-FUEL TRANSFER, ACT		152	28-28-33
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166QM2	VALVE-FUEL INLET, ACT2	826AR	150	28-10-00
167QM2	VALVE-VENT, ACT2	826AR	150	28-10-00
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170QM1	PROTECTOR-OVERPRESSURE, ACT1	826AR	150	28-10-00
172QM1	VALVE-INWARD PRESSURE RELIEF, ACT1	826AR	150	28-10-00
173QM1	FUEL DRAIN VALVE		152	28-10-00
177QM1	CHECK VALVE-ACT PRESSURIZATION		150	28-10-00
179QM	CHECK VALVE-CABIN AIR INTAKE, ACT PRESSURIZATION		152	28-28-43
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171QM	VALVE-PRESSURE REDUCING, ACT1		152	28-28-42
176QM	CHECK VALVE-ACT TRANSFER		141	28-28-41
178QM	CHECK VALVE-ACT PRESSURIZATION		152	28-28-38
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179QM	CHECK VALVE-CABIN AIR INTAKE, ACT PRESSURIZATION		152	28-28-43
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170QM2	PROTECTOR-OVERPRESSURE, ACT2	826AR	150	28-10-00
172QM2	VALVE-INWARD PRESSURE RELIEF, ACT2	826AR	150	28-10-00
173QM2	VALVE-FUEL DRAIN, ACT2	826AR	152	28-10-00
177QM2	CHECK VALVE-ACT2		150	28-10-00
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180QM1	VALVE-REFUEL RESTRICTOR, ACT1		150	28-10-00
183QM	AIR FILTER-CABIN INTAKE, ACT PRESSURIZATION		152	28-28-39
184QM	LEAK MONITOR-PIPES, ACT		152	28-28-44
185QM	LEAK MONITOR-ACT	826AR	152	28-10-00
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183QM	AIR FILTER-CABIN INTAKE, ACT PRESSURIZATION		152	28-28-39
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180QM2	VALVE-REFUEL RESTRICTOR, ACT2		150	28-10-00
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191QM1	VALVE-PRESSURE HOLDING, ACT1		150	28-28-48
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191QM2	VALVE-PRESSURE HOLDING, ACT2		150	28-28-48
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226QM1	VALVE-WATER DRAIN, ACT1		152	28-21-52
226QM2	VALVE-WATER DRAIN, ACT2		152	28-21-52
227QM1	VALVE-FUEL DRAIN, ACT1		152	28-21-52
227QM2	VALVE-FUEL DRAIN, ACT2		152	28-21-52
228QM1	VALVE-FUEL INLET, ACT1		151	28-10-00
228QM2	VALVE-FUEL INLET, ACT2		151	28-21-52
229QM1	VALVE-INWARD PRESSURE RELIEF, ACT1		151	28-21-52
229QM2	VALVE-INWARD PRESSURE RELIEF, ACT2		151	28-21-52
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236QM	VALVE-ISOLATION, FWD ACT		151	28-28-61
237QM	VALVE-THERMAL RELIEF, FWD ACT TRANSFER		151	28-28-46
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230QM1	VALVE-REFUEL RESTRICTOR, ACT1		151	28-21-52
230QM2	VALVE-REFUEL RESTRICTOR, ACT2		151	28-21-52
231QM1	CHECK-VALVE-ACT1		152	28-10-00
233QM	VALVE-AIR SHUT OFF, ACT		152	28-10-00
234QM	VALVE-VENT, ACT		152	28-28-62
238QM	VALVE-THERMAL RELIEF, ACT TRANSFER		151	28-28-46
239QM	CHECK VALVE-ACT VENT, AFT		152	28-28-63
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240QM	CHECK VALVE-ACT VENT, FWD		152	28-28-63
241QM	VALVE-PRESSURE HOLDING, FWD ACT		152	28-28-49
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242QM	VALVE-PRESSURE HOLDING, ACT		152	28-28-49
243QM	VALVE-PRESSURE HOLDING, AFT ACT		152	28-28-49
245QM	VALVE-FUEL DRAIN, ACT		152	28-28-05
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257QM	PROTECTOR-OVERPRESSURE, FWDACT		152	28-12-42
** ON A/C NOT FOR ALL
254QM	LEAK MONITOR-ACT, AFT		152	28-10-00
255QM	LEAK MONITOR-PIPES, AFT ACT		152	28-10-00
256QM	PROTECTOR-OVERPRESSURE, AFTACT		152	28-12-42

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4. System Description

ACT Transfer System - Component Location ** ON A/C NOT FOR ALL

ACT Transfer System AFT Cargo Compartment - Component Location ** ON A/C NOT FOR ALL

ACT Pressurization System - Component Location ** ON A/C NOT FOR ALL

ACT Transfer System - Component Location ** ON A/C NOT FOR ALL

ACT Transfer System AFT Cargo Compartment - Component Location ** ON A/C NOT FOR ALL

ACT Pressurization System - Component Location ** ON A/C NOT FOR ALL

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5. System Description
The ACT transfer system is divided into the following sub-systems:

an additional center tank (ACT) (Ref. AMM D/O 28-11-00-00),
a fuel transfer system,
a vent system (Ref. AMM D/O 28-12-00-00),
a pressurization system.

A. ACT1
The ACT1 is installed between FR47.2 and FR47.5 in the cargo compartment. It has a structural container in which a flexible bladder tank is attached to all internal surfaces. The structural container is the same size as a full width cargo container.

A drain line connects the space between the ACT bladder tank and the ACT structure to the aircraft drain mast. A second drain line connects the shrouded refuel/defuel line and vent line to the aircraft drain mast. If a fuel leak occurs in the ACT bladder tank or in a shrouded line, the fuel will go through the drain to atmosphere. The drain lines have leak monitors 185QM (Ref. 28-11-00) and 184QM. Maintenance personnel can use the leak monitors to do a check that there is no fuel leakage in the ACT bladder or shrouded lines.
The ACT transfer system is divided into the following sub-systems:

two additional center tanks (ACT1 and ACT2) (Ref. AMM D/O 28-11-00-00),
a fuel transfer system,
a vent system (Ref. AMM D/O 28-12-00-00),
a pressurization system.

B. Additional Center Tank (ACT)
The ACT1 and ACT2 are installed in the aft cargo-compartment between FR47.2 and FR53. Each ACT is a structural container in which a flexible bladder tank is attached to all internal surfaces. The structural containers have the same size as a full width cargo container.

A drain line connects the space between each ACT bladder tank and each ACT structural container to the aircraft drain mast. A second drain line connects the shrouded refuel/defuel line and vent line to the aircraft drain mast. If a fuel leak occurs on the ACT bladder tank or on a shrouded line, the fuel will go through the drain to the atmosphere. The drain lines have leak monitors 185QM and 184QM (Ref. AMM D/O 28-11-00-00).
Maintenance personnel must use the leak monitors to do a leak check, to make sure that there is no fuel leakage on the ACT bladder or on the shrouded lines.
The ACT transfer system has the following sub-systems:

The ACT(s) (Ref. AMM D/O 28-11-00-00)
The fuel transfer system
The venting system (Ref. AMM D/O 28-12-00-00)
The pressurization system
The quantity indicating system (Ref. AMM D/O 28-42-00-00)
The fuel-level sensing system (Ref. AMM D/O 28-46-00-00).

C. ACT(s)
The ACT FWD can be installed between FR35.1 and FR 35.4 in the forward cargo compartment.
The ACT AFT1 and the ACT AFT2 can be installed between FR47.2 and FR50 in the aft cargo compartment.

Each ACT is a structural container with a flexible bladder tank attached to all internal surfaces. The structural containers are in the same size as a full width cargo container.

A cavity drain line connects the space between each ACT bladder tank and each ACT structural container to the aircraft drain mast. The second drain line connects the shrouded fuel line and vent line to the aircraft drain mast.

ACT(s) has (have) two water drain terminations. They are in positions forward and aft, one either side of the aircraft center line. The drains within the ACT(s) are connected by a channel so that only one valve controls flow from the two drains.

If a fuel leak occurs in an ACT bladder tank or in a shrouded line, the fuel will go through the drain mast to the atmosphere. The drain lines have leak monitors 253QM, 254QM and 255QM (Ref. AMM D/O 28-11-00-00). Maintenance personnel must use the leak monitors to make sure that there is no fuel leakage in the ACT bladder or shrouded lines.
ACT AFT1 and ACT AFT2 can be installed between FR47.2 and FR50 in the aft cargo compartment.
Each ACT is a structural container with a flexible bladder tank attached to all internal surfaces. The structural containers are in the same size as a full width cargo container.
A cavity drain line connects the space between each ACT bladder tank and each ACT structural container to the aircraft drain mast. The second drain line connects the shrouded fuel line and vent line to the aircraft drain mast.
ACT(s) has (have) two water drain terminations. They are in positions forward and aft, one either side of the aircraft center line. The drains within the ACT(s) are connected by a channel so that only one valve controls flow from the two drains.
If a fuel leak occurs in an ACT bladder tank or in a shrouded line, the fuel will go through the drain mast to the atmosphere. The drain lines have leak monitors 254QM and 255QM (Ref. AMM D/O 28-11-00-00). Maintenance personnel must use the leak monitors to make sure that there is no fuel leakage in the ACT bladder or shrouded lines.

D. Fuel Transfer System
The fuel transfer system has these components:

an ACT fuel pump pressure switch (2QH),
an ACT fuel pump (1QH) and its related mounting plate (163QM),
an ACT fuel transfer valve (165QM) and its related electrical actuator (6QH),
an ACT1 fuel inlet valve (166QM1) and its related electrical actuator (5QH1),
an ACT transfer thermal relief valve (169QM),
an ACT1 refuel restrictor valve (180QM1),
a check valve (176QM),
a shrouded fuel transfer line.

The ACT transfer pump 1QH and the ACT transfer pump pressure switch 2QH are installed at the rear spar FR42. The pump operates when the manual forward transfer is selected.
The pressure switch monitors the fuel pressure downstream of the ACT fuel transfer pump 1QH. When one low level sensor in ACT1 is dry for more than 240 seconds the pressure switch is given a signal (if the aircraft is in flight). A warning appears on the EWD and on the pushbutton switch. The pushbutton switch must be switched off.

The ACT fuel transfer valve (165QM) is installed at the rear spar FR42 in the fuel line to the center tank. The actuator (6QH) opens the valve when an automatic or manual fuel forward transfer is selected.

The ACT1 fuel inlet valve (166QM1) is installed inside the ACT in the fuel line. The actuator (5QH1) opens the valve when an automatic, manual fuel forward transfer or refuel is selected.

The ACT refuel valve (41QU) is installed at the rear spar FR42 in the fuel line to the main fuel gallery. The integral solenoid opens the valve during refuel (Ref. AMM D/O 28-25-00-00).

A refuel restrictor valve 180QM1 is installed in the fuel line inside the ACT1. This valve makes sure that the refuel rate of the ACT1 is within a safe limit, but it will not limit the defuel rate of the ACT1.

A shrouded fuel transfer line connects the ACT with the center tank. It transfers the fuel from the ACT to the center tank when automatic or manual forward transfer is selected.

E. Fuel Transfer System

ACT Transfer System - Block Diagram ** ON A/C NOT FOR ALL

The fuel transfer system has these components:

an ACT fuel pump pressure switch (2QH),
an ACT fuel pump (1QH) and its related mounting plate (163QM),
an ACT fuel transfer valve (165QM) and its related electrical actuator (6QH),
an ACT1 fuel inlet valve (166QM1) and its related electrical actuator (5QH1),
an ACT2 fuel inlet valve (166QM2) and its related electrical actuator (5QH2),
an ACT transfer thermal relief valve (169QM),
an ACT1 refuel restrictor valve (180QM1),
an ACT2 refuel restrictor valve (180QM2),
a check valve (176QM),
a shrouded fuel transfer line.

The ACT transfer pump 1QH and the ACT transfer pump of the pressure switch 2QH are installed at the rear spar FR42. The pump operates when the manual forward fuel transfer p/bsw is selected.
The pressure switch monitors the fuel pressure downstream of the ACT fuel transfer pump 1QH. When one low level sensor in ACT1 is dry for more than 240 seconds the pressure switch is given a signal (if the aircraft is in flight). A warning appears on the EWD and on the pushbutton switch. The pushbutton switch must be switched off.

The ACT fuel transfer valve (165QM) is installed at the rear spar FR42 in the fuel line to the center tank. The actuator (6QH) opens the valve when an automatic or manual forward fuel transfer is selected.

The ACT1 fuel inlet valve (166QM1) and the ACT2 fuel inlet valve (166QM2) are installed inside the related ACT in the fuel line. The actuator (5QH1 or 5QH2) opens the related valve when an automatic, manual forward fuel transfer or refuel is selected.

The ACT refuel valve (41QU) is installed at the rear spar FR42 in the fuel line to the refuel gallery. The integral solenoid opens the valve during refuel (Ref. AMM D/O 28-25-00-00).

A refuel restrictor valve 180QM1 (180QM2) is installed in the fuel line inside the ACT1 (ACT2) . This valve makes sure that the refuel rate of the ACT1 or ACT2 is within a safe limit, but it will not limit the defuel rate of the ACT1 and the ACT2. Restrictors downstream of the fuel pump (1QH) and the ACT transfer check valve limit the transfer defuel rate of the ACT1 and ACT2.

A shrouded fuel transfer line connects the ACT1 and ACT2 with the center tank. It transfers the fuel from each ACT to the center tank when automatic or manual forward fuel transfer is selected.

F. Fuel Transfer System

ACT Transfer System - FWD Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

The fuel transfer system has these components:

ACT pressure switch 2QH
ACT fuel transfer pump 1QH and its related mounting plate 163QM
ACT transfer valve 165QM and its related electrical actuator 6QH
Fuel inlet valve 228QM1 and its related electrical actuator 94QH1 (if ACT AFT1 installed)
Fuel inlet valve 228QM2 and its related electrical actuator 94QH2 (if ACT AFT2 installed)
Fuel inlet valve 228QM4 and its related electrical actuator 94QH4 (if ACT FWD installed)
Forward ACT isolation-valve 236QM and its related actuator 92QH
Forward ACT vent-isolation-valve 232QM and its related actuator 93QH
Two ACT thermal-relief-valves 237QM and 238QM
Refuel restrictor valve 230QM1 (if ACT AFT1 installed)
Refuel restrictor valve 230QM2 (if ACT AFT2 installed)
Refuel restrictor valve 230QM4 (if ACT FWD installed)
ACT transfer check valve 176QM
Shrouded fuel transfer line.

ACT fuel transfer pump 1QH and its related pressure switch 2QH are installed at FR42. The ACT fuel transfer pump can be used on the ground for maintenance purpose. In flight it can be used as backup solution, in case of that the automatic fuel transfer from the ACT, controlled by cabin pressure, fails. The ACT fuel transfer pump operates, when on overhead panel 28VU:

The ACT XFR MODE SEL pushbutton switch is pushed (the MAN legend is on)
The one ACT is selected on the ACT XFR rotary switch.

The pressure switch monitors the fuel pressure downstream of ACT fuel transfer pump 1QH. When the pressure switch detects a low pressure for more than 60 seconds (and the selected ACT is empty with the aircraft in flight) a warning appears on the EWD and the ACT XFR MODE SEL pushbutton switch must be switched off.

ACT transfer valve 165QM is installed at FR42 in the fuel line to the center tank. Transfer valve actuator 6QH opens the valve for requested automatic or manual fuel transfer from the ACT(s). The fuel transfer valve is always open and only closes when you select refuel or push on the O/FLOW pushbutton switch. Then, the valve can be open if you select manual fuel transfer.

ACT fuel inlet valves 228QM1, 228QM2 and 228QM4 are installed inside the related ACT in the fuel line. Actuators 94QH1, 94QH2 and 94QH4 open the related valve when an automatic fuel transfer, manual fuel transfer or refuel is selected.

ACT refuel valve 41QU is installed at FR42 in the fuel line to the main fuel gallery. The integral solenoid opens the valve during the refuel procedure (Ref. AMM D/O 28-25-00-00) if different interlocks are satisfied.

Refuel restrictor valves 230QM1, 230QM2 and 230QM4 are installed in the fuel line inside the related ACT. These valves make sure that the refuel rate of the ACT is within safe limits, but they will not limit the defuel rate of the ACT.

A shrouded fuel transfer line connects the ACT with the center tank. It transfers the fuel from each ACT to the center tank when automatic or manual fuel transfer is selected.

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

The fuel transfer system has these components:

ACT pressure switch (2QH)
ACT fuel transfer-pump (1QH) and its related mounting plate (163QM)
ACT transfer valve (165QM) and its related electrical actuator (6QH)
Fuel inlet valve (228QM1) and its related electrical actuator (94QH1) (if ACT AFT1 installed)
Fuel inlet valve (228QM2) and its related electrical actuator (94QH2) (if ACT AFT2 installed)
ACT thermal relief-valve (238QM)
Refuel restrictor valve (230QM1) (if ACT AFT1 installed)
Refuel restrictor valve (230QM2) (if ACT AFT2 installed)
ACT transfer check-valve (176QM)
Shrouded fuel transfer line.

The ACT fuel transfer-pump (1QH) and its related pressure switch (2QH) are installed at FR42. The ACT fuel transfer-pump can be used on the ground for maintenance purpose. In flight it can be used as backup solution, in case of that the automatic fuel transfer from the ACT, controlled by cabin pressure, fails. The ACT fuel transfer pump operates, when on overhead panel 28VU:

The ACT XFR MODE SEL pushbutton switch is pushed (the MAN legend is on)
The one ACT is selected on the ACT XFR rotary switch.

The pressure switch monitors the fuel pressure downstream of the ACT fuel transfer-pump (1QH). When the pressure switch detects a low pressure for more than 60 seconds (and the selected ACT is empty with the aircraft in flight) a warning appears on the EWD and the ACT XFR MODE SEL pushbutton switch must be switched off.
The ACT transfer valve (165QM) is installed at FR42 in the fuel line to the center tank. The transfer valve actuator (6QH) opens the valve for requested automatic or manual fuel transfer from the ACT(s). The fuel transfer valve is always open and only closes when you select refuel or push on the O/FLOW pushbutton switch. Then, the valve can be open if you select manual fuel transfer.
The fuel inlet valves (228QM1 and 228QM2) are installed inside the related ACT in the fuel line. Actuators (94QH1 and 94QH2) open the related valve when an automatic fuel transfer, manual fuel transfer or refuel is selected.
The ACT refuel valve (41QU) is installed at FR42 in the fuel line to the main fuel gallery. The integral solenoid opens the valve during the refuel procedure (Ref. AMM D/O 28-25-00-00) if different interlocks are satisfied.
The refuel restrictor valves (230QM1 and 230QM2) are installed in the fuel line inside the related ACT. These valves make sure that the refuel rate of the ACT is within safe limits, but they will not limit the defuel rate of the ACT.
A shrouded fuel transfer line connects the ACT with the center tank. It transfers the fuel from each ACT to the center tank when automatic or manual fuel transfer is selected.

G. Vent System
The vent system of the ACT has:

an ACT1 vent valve (167QM1) and its related electrical actuator (4QH1),
an inward pressure relief valve (172QM1) (Ref. AMM D/O 28-12-00-00),
an overpressure protector (170QM1) (Ref. AMM D/O 28-12-00-00),
a fuel drain valve (173QM1) (Ref. AMM D/O 28-12-00-00),
a pressure holding valve (191QM1) (Ref. 28-28-48),
a shrouded ACT vent line.

The actuator 4QH1 closes the ACT1 vent valve 167QM1 to pressurize the ACT1 for automatic fuel transfer.

The inward pressure relief valve 172QM1 (Ref. AMM D/O 28-12-00-00) prevents excessive inward pressure on the bladder bag (190QM1) during descent and emergency descent.

The overpressure protector 170QM1 (Ref. AMM D/O 28-12-00-00) installed in the vent line depressurizes the ACT through the vent line if the tank pressure is too high.

The shrouded ACT vent line connects the ACT to the air-space at the top of the center tank. The center tank air-space is ventilated to atmosphere by the tank venting system (Ref. AMM D/O 28-12-00-00).

H. Vent System
The vent system of the ACT has:

an ACT1 vent valve (167QM1) and its related electrical actuator (4QH1),
an ACT2 vent valve (167QM2) and its related electrical actuator (4QH2),
an inward pressure relief valve (172QM1) and (172QM2) (Ref. AMM D/O 28-12-00-00),
an overpressure protector (170QM1) and (170QM2) (Ref. AMM D/O 28-12-00-00),
a fuel drain valve (173QM1) and (173QM2) (Ref. AMM D/O 28-12-00-00),
a pressure holding valve (191QM1) and (191QM2) (Ref. 28-28-48),
a shrouded ACT vent line.

The actuator 4QH1 (4QH2) closes the ACT1 (ACT2) vent valve 167QM1 (167QM2) to pressurize the ACT1 (ACT2) for automatic fuel transfer.

The inward pressure relief valve 172QM1 and (172QM2) (Ref. AMM D/O 28-12-00-00) prevents excessive inward pressure on the bladder bag 190QM1 and (190QM2) during descent and emergency descent.

The overpressure protector 170QM1 and (170QM2) (Ref. AMM D/O 28-12-00-00) installed in the vent line in each ACT depressurizes the related ACT through the vent line if the tank pressure is too high.

The shrouded ACT vent line connects the ACT to the air-space at the top of the center tank. The center tank air-space is ventilated to atmosphere by the tank venting system (Ref. AMM D/O 28-12-00-00).

I. Vent System
The vent system of the ACT(s) has these components:

Fuel drain valves 227QM1 (if ACT AFT1 installed), 227QM2 (if ACT AFT2 installed) and 227QM4 (if ACT FWD installed)
ACT vent valve 234QM and its related actuator 91QH
Inward pressure relief-valves 229QM1 (if ACT AFT1 installed), 229QM2 (if ACT AFT2 installed) and 229QM4 (if ACT FWD installed) (Ref. AMM D/O 28-12-00-00)
Overpressure protectors 256QM, 257QM and 258QM (if ACT FWD installed) (Ref. AMM D/O 28-12-00-00)
Pressure holding valves 241QM, 242QM and 243QM
Fuel drain valve 245QM
Forward ACT vent-isolation-valve 232QM and its related actuator 93QH.

The ACT vent valve 234QM is installed in the center tank. It automatically closes when the aircraft is in flight. The vent valve does not open again until the weight-on conditions are correct. Then, the valve can be closed when you select manual transfer.

Inward pressure relief-valves 229QM1, 229QM2 and 229QM4 (Ref. AMM D/O 28-12-00-00) prevent too much inward pressure on the flexible bladder tanks during descent.

Overpressure protectors 256QM and 257QM (Ref. AMM D/O 28-12-00-00) installed in the vent line, break at the specified value to release the pressure, when the air pressure in the ACT vent pipe is too high.

Three pressure holding valves 241QM, 242QM and 243QM are installed in the vent line. The pressure holding valves prevent high pressures in the ACT(s) as the aircraft climbs. The valves release the pressure into the center tank vent-line at a maximum pressure difference of 0.664 bar (10 psi). Two pressure holding valves (241QM and 243QM) are on the ACT side of the check valves. One pressure holding valve (242QM) is between the check valves, on the ACT side of the vent valve.

The forward ACT sub-system goes through the rotor burst zone. This is connected with a detection wire that controls forward ACT isolation-valve 236QM, forward vent isolation-valve 232QM and the inlet valve of ACT FWD. Forward ACT isolation valve 236QM and forward vent isolation-valve 232QM stay open until the detection wire is broken. Also, when the inlet valve of ACT FWD is open, it closes automatically if the detection wire breaks. If the forward ACT vent isolation valve fails closed during refuel and the refuel interlock fails, then overpressure protector 258QM breaks from ACT FWD into the vent line. This protects the ACT FWD structure.

The shrouded ACT vent line connects the ACT to the air-space at the top of the center tank. The center tank air-space is ventilated to atmosphere by the tank venting system (Ref. AMM D/O 28-12-00-00).
The vent system of the ACT(s) has these components:

Fuel drain valves (227QM1 (if ACT AFT1 installed) and 227QM2 (if ACT AFT2 installed))
ACT vent valve (234QM) and its related actuator (91QH)
Inward pressure relief-valves (229QM1 (if ACT AFT1 installed) and 229QM2 (if ACT AFT2 installed)) (Ref. AMM D/O 28-12-00-00)
Overpressure protector (256QM) (Ref. AMM D/O 28-12-00-00)
Pressure holding valves (242QM and 243QM)
Fuel drain valve (245QM).

The ACT vent valve (234QM) is installed in the center tank. It automatically closes when the aircraft is in flight. The vent valve does not open again until the weight-on conditions are correct. Then, the valve can be closed when you select manual transfer.
Inward pressure relief-valves (229QM1 and 229QM2) (Ref. AMM D/O 28-12-00-00) prevent too much inward pressure on the flexible bladder tanks during descent.
Overpressure protector (256QM) (Ref. AMM D/O 28-12-00-00) installed in the vent line, break at the specified value to release the pressure, when the air pressure in the ACT vent pipe is too high.
Two pressure holding valves (242QM and 243QM) are installed in the vent line. The pressure holding valves prevent high pressures in the ACT(s) as the aircraft climbs. The valves release the pressure into the center tank vent-line at a maximum pressure difference of 0.664 bar (10 psi). One pressure holding valves (243QM) is on the ACT side of the check valves. One pressure holding valve (242QM) is between the check valves, on the ACT side of the vent valve.
The shrouded ACT vent line connects the ACT to the air space at the top of the center tank. The center tank air-space is ventilated to atmosphere by the tank venting system (Ref. AMM D/O 28-12-00-00).

J. Pressurization System
The primary components of the ACT pressurization system are:

the cabin intake air-filter (183QM),
three check valves (177QM, 178QM, 179QM),
the ACT air shut-off valve (168QM) and the related electrical actuator (3QH),
the pressure reducing valve (171QM).

The ACT air shutoff valve (168QM) is installed in the pressurization line of the ACT. The applicable actuator (3QH) opens the ACT air shutoff valve with automatic forward fuel transfer. The cabin air pressure (pressurized from the pressure control system) enters the ACT through the pressurization line and transfers the fuel from the ACT to the center tank. The pressure reducing valve (171QM) is installed in the pressurization line. The pressure reducing valve regulates pressurization of the ACT to about 0.195 bar (2.8282 psi) over the ambient air pressure. The ACT pressurization system has three check valves. These check valves prevent that fuel vapor from the ACT can enter the cabin. The filter in the ACT pressurization system makes sure that only clean air goes into the fuel tank.

K. Pressurization System

ACT Transfer System - Block Diagram ** ON A/C NOT FOR ALL

In the pressurization system the following components are installed:

a cabin intake air-filter (183QM),
four check valves (177QM1, 177QM2, 178QM, 179QM),
an ACT air shut-off valve (168QM) and its related electrical actuator (3QH),
a pressure reducing valve (171QM).

The ACT air shutoff valve 168QM is installed in the ACT pressurization line. The actuator 3QH opens the valve when the automatic forward fuel transfer is selected. This activates the pressurization system and the air pressure in the cabin (pressurized from the pressure control system) enters the ACT(s) through the pressurization line and transfers the fuel from the ACT(s) to the center tank. In the pressurization line is a pressure reducing valve 171QM which regulates the ACT pressurization supply to about 0.195 bar (2.83 psi) over ambient air pressure. It also has check valves which prevent the vapor from the ACT(s) entering the cabin. The pressurization line has a filter to make sure that clean air goes into the tank.

L. Pressurization System

ACT Pressurization System - Component Location ** ON A/C NOT FOR ALL

The pressurisation system of the ACT has these components:

Cabin-intake air-filter 183QM
Two check valves 178QM, 179QM
ACT air-shut-off valve 233QM and its related electrical actuator 90QH
Pressure reducing valve 171QM.

ACT air shut-off valve 233QM is installed in the pressurisation line of the ACT. Actuator 90QH opens the valve when the aircraft is in flight. This operates the pressurisation system and the air pressure in the cabin (pressurized from the pressure control system) goes into the ACT(s) through the pressurisation line via ACT AFT1 and ACT FWD and transfers the fuel from the ACT to the center tank. In the pressurisation line there is pressure reducing valve 171QM which adjusts the ACT pressurisation supply to between 0.345 +-0 bar or -+0.103 bar (5.0038 ++0.0000 psi or -+1.4939 psi) above ambient air pressure. It also has check valves which prevent the vapour from the ACT going into the cabin. The pressurisation line has a filter to make sure that clean air goes into the tank.

ACT Pressurization System - Component Location ** ON A/C NOT FOR ALL

The pressurisation system of the ACT has these components:

Cabin intake air-filter (183QM)
Two check valves (178QM and 179QM)
ACT air-shut-off valve (233QM) and its related electrical actuator 90QH
Pressure reducing valve (171QM).

The ACT air-shut-off valve (233QM) is installed in the pressurization line of the ACT. The actuator (90QH) opens the valve when the aircraft is in flight. This operates the pressurization system and the air pressure in the cabin (pressurized from the pressure control system) goes into the ACT(s) through the pressurization line via ACT AFT1 and transfers the fuel from the ACT to the center tank. In the pressurization line there is pressure reducing valve (171QM) which adjusts the ACT pressurization supply to between 0.345 -0 bar or +0.103 bar (5.00 -0 psi or +1.49 psi) above ambient air pressure. It also has check valves which prevent the vapour from the ACT going into the cabin. The pressurization line has a filter to make sure that clean air goes into the tank.

M. Valve/Pump Status

(1) Aircraft on Ground
When the aircraft is on the ground the ACT automatic transfer system is inoperative and (if the crew take no action) the:

ACT fuel transfer valve 165QM is closed,
ACT air shut-off valve 168QM is closed,
ACT1 vent valve 167QM1 is open,
ACT1 fuel inlet valve 166QM1 is closed,
ACT refuel valve 41QU is closed,
the ACT transfer pump 1QH does not operate.

N. Valve Pump Status

(1) Aircraft on Ground
When the aircraft is on the ground the ACT automatic transfer system is inoperative and (if the crew takes no action) the:

ACT fuel transfer valve 165QM is closed,
ACT air shut-off valve 168QM is closed,
ACT1 vent valve 167QM1 is open,
ACT2 vent valve 167QM2 is open,
ACT1 fuel inlet valve 166QM1 is closed,
ACT2 fuel inlet valve 166QM2 is closed,
ACT refuel valve 41QU is closed,
ACT transfer pump 1QH does not operate.

O. Valve/Pump Status

(1) Aircraft on ground

ACT Transfer System - FWD Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

When the aircraft is on the ground the ACT automatic transfer system is off and the:

NOTE: The transfer system is automatically controlled OFF unless it is overridden by selection of the manual transfer mode. Automatic transfer is not available until the tanks are pressurized.

ACT transfer valve 165QM is open (except during refuel)
ACT air shut-off valve 233QM is closed
Fuel inlet-valve 228QM1 is closed (if ACT AFT1 installed)
Fuel inlet-valve 228QM2 is closed (if ACT AFT2 installed)
Fuel inlet-valve 228QM4 is closed (if ACT FWD installed)
ACT refuel valve 41QU is closed
Vent valve 234QM in the center tank is open
Forward ACT isolation-valve 236QM is open
Forward ACT vent isolation-valve 232QM is open
ACT transfer pump 1QH does not operate.

(2) Aircraft on ground

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

When the aircraft is on the ground the ACT automatic transfer system is off and the:

NOTE: The transfer system is automatically controlled OFF unless it is overridden by selection of the manual transfer mode. Automatic transfer is not available until the tanks are pressurized.

ACT transfer valve (165QM) is open (except during refuel)
ACT air-shut-off valve (233QM) is closed
Fuel inlet valve (228QM1) is closed (if ACT AFT1 installed)
Fuel inlet valve (228QM2) is closed (if ACT AFT2 installed)
ACT refuel valve (41QU) is closed
Vent valve (234QM) in the center tank is open
ACT transfer pump (1QH) does not operate.

P. Valve/Pump Status

(1) Automatic Forward Transfer
The ACT fuel level sensing system and the air pressure in the cabin-compartment operates the automatic fuel forward transfer and the:

ACT fuel transfer valve 165QM is open,
ACT air shut-off valve 168QM is open,
ACT1 vent valve 167QM1 is closed,
ACT1 fuel inlet valve 166QM1 is open,
ACT refuel valve 41QU is closed,
the ACT transfer pump 1QH does not operate.

(2) Automatic Forward Fuel Transfer with two ACT installed
The ACT fuel level sensing system and the air pressure in the cabin-compartment operate the automatic fuel forward transfer and the:

ACT fuel transfer valve 165QM is open,
ACT air shut-off valve 168QM is open,
ACT1 vent valve 167QM1 is closed,
ACT2 vent valve 167QM2 is closed,
ACT1 fuel inlet valve 166QM1 is closed,
ACT2 fuel inlet valve 166QM2 is open,
ACT refuel valve 41QU is closed,
ACT transfer pump 1QH does not operate.

When the ACT2 is empty:

ACT fuel transfer valve 165QM is open,
ACT air shut-off valve 168QM is open,
ACT1 vent valve 167QM1 is closed,
ACT2 vent valve 167QM2 is closed,
ACT1 fuel inlet valve 166QM1 is open,
ACT2 fuel inlet valve 166QM2 is closed,
ACT refuel valve 41QU is closed,
ACT transfer pump 1QH does not operate.

(3) Automatic fuel transfer with three ACTs installed
The ACT fuel level sensing system and the air pressure in the forward and aft cargo compartment operate the automatic fuel transfer and the:

ACT transfer valve 165QM is open
ACT air shut-off valve 233QM is open (auto)
ACT AFT1 fuel-inlet valve 228QM1 is closed (auto)
ACT AFT2 fuel-inlet valve 228QM2 is closed (auto)
ACT FWD fuel-inlet valve 228QM4 is open (auto)
ACT refuel valve 41QU is closed
ACT vent valve 234QM in the center tank is closed
Forward ACT isolation-valve 236QM is open
Forward ACT vent-isolation-valve 232QM is open
ACT transfer pump 1QH does not operate.

When the ACT FWD is empty:

ACT fuel-transfer valve 165QM is open
ACT air shut-off valve 233QM is open (auto)
ACT AFT1 fuel-inlet valve 228QM1 is closed (auto)
ACT AFT2 fuel-inlet valve 228QM2 is open (auto)
ACT FWD fuel-inlet valve 228QM4 is closed (auto)
ACT refuel valve 41QU is closed
ACT vent valve 234QM in the center tank is closed
Forward ACT isolation-valve 236QM is open
Forward ACT vent-isolation-valve 232QM is open
ACT transfer pump 1QH does not operate.

NOTE: This sequence continues until the fuel from all the ACTs is removed in the order that follows: ACT FWD, ACT AFT2 and ACT AFT1.

(4) Automatic fuel transfer with two ACTs installed
The ACT fuel level sensing system and the air pressure in the aft cargo compartment operate the automatic fuel transfer and the:

ACT transfer valve (165QM) is open
ACT air-shut-off valve (233QM) is open (auto)
Fuel inlet valve (228QM1) (if ACT AFT1 is installed) is closed (auto)
Fuel inlet valve (228QM2) (if ACT AFT2 is installed) is closed (auto)
ACT refuel valve (41QU) is closed
ACT vent valve (234QM) in the center tank is closed
ACT transfer pump (1QH) does not operate.

NOTE: This sequence continues until the fuel from all the ACTs is removed in the order of ACT AFT2 and ACT AFT1.

(5) Manual Forward Transfer
For ground transfer (manual fuel forward transfer), you have to push the ACT pushbutton switch 24QH on the overhead FUEL panel 40VU (the FWD legend comes on). This starts the ACT manual forward transfer and:

the ACT fuel transfer valve 165QM is open,
the ACT1 fuel inlet valve 166QM1 is open,
ACT refuel valve 41QU is closed,
the ACT transfer pump 1QH operates.

(6) Manual Forward Fuel Transfer with Two ACT Installed
For the manual forward fuel transfer with the aircraft on ground , you must push the ACT pushbutton switch 24QH on the overhead FUEL panel 40VU (the FWD legend comes on). This starts the manual forward fuel transfer of the ACT and:

the ACT fuel transfer valve 165QM is open,
the ACT1 fuel inlet valve 166QM1 is closed,
the ACT2 fuel inlet valve 166QM2 is open,
the ACT refuel valve 41QU is closed,
the ACT transfer pump 1QH operates.

When the ACT2 is empty:

the ACT2 fuel inlet valve 166QM2 is closed,
the ACT fuel transfer valve 165QM is open,
the ACT1 fuel inlet valve 166QM1 is open,
the ACT refuel valve 41QU is closed,
the ACT transfer pump 1QH operates.

(7) Manual fuel transfer with three ACTs installed

Cockpit Overhead Fuel Panel ** ON A/C NOT FOR ALL

ACT Transfer System - FWD Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

For the manual fuel transfer with the aircraft on ground, on the ACT control panel 28VU, you must:

Push the ACT XFR MODE SEL pushbutton switch (the MAN legend comes on)
Turn the ACT XFR rotary switch to the required ACT position.

This starts the manual fuel transfer from the selected ACT.
If the ACT AFT2 is the selected tank the:

Air shut-off valve 233QM is open
ACT vent valve 234QM is closed
ACT fuel transfer valve 165QM is open
ACT AFT1 and ACT FWD fuel inlet valves 228QM1, 228QM4 are closed
ACT AFT2 fuel inlet valve 228QM2 is open
ACT refuel valve 41QU is closed
ACT fuel transfer pump 1QH operates.

When the ACT AFT2 is empty the:

Transfer pump LO PR ECAM warning appears
Crew must deselect manual transfer
ACT AFT1 fuel drains by auto transfer.

NOTE: Manual transfer does not override the forward ACT isolation valve (236QM) to open if a failure occurs.

(8) Manual fuel transfer with two ACTs installed

Cockpit Overhead Fuel Panel ** ON A/C NOT FOR ALL

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

For the manual fuel transfer with the aircraft on ground, on the ACT control panel 28VU, you must:

Push the ACT XFR MODE SEL pushbutton switch (the MAN legend comes on)
Turn the ACT XFR rotary switch to the required ACT position.

This starts the manual fuel transfer from the selected ACT. If the ACT AFT2 is the selected tank the:

ACT air-shut-off valve (233QM) is open
ACT vent valve (234QM) is closed
ACT fuel transfer-valve (165QM) is open
Fuel inlet valve (228QM1) (if ACT AFT1 is installed) is closed
Fuel inlet valve (228QM2) (if ACT AFT2 is installed) is open
ACT refuel valve (41QU) is closed
ACT fuel transfer-pump (1QH) operates.

When the ACT AFT2 is empty the:

Transfer pump LO PR ECAM warning appears
Crew must deselect manual transfer
ACT AFT1 fuel drains by auto transfer.

(9) ACT Refuel (Ref. AMM D/O 28-25-00-00)
The ACT is refueled at the same time as the other aircraft tanks. During the refuel of the ACT:

the ACT fuel transfer valve 165QM is closed,
the ACT air shut-off valve 168QM is closed,
the ACT1 vent valve 167QM1 is open,
the ACT1 fuel inlet valve 166QM1 is open,
the ACT refuel valve 41QU is open,
the ACT transfer pump 1QH does not operate.

(10) ACT Refuel (Ref. AMM D/O 28-25-00-00)
The ACT(s) are refueled at the same time as the other aircraft tanks. During the refuel of the ACT:

the ACT fuel transfer valve 165QM is closed,
the ACT air shut-off valve 168QM is closed,
the ACT1 vent valve 167QM1 is open,
the ACT1 fuel inlet valve 166QM1 is open,
the ACT2 vent valve 167QM2 is open,
the ACT2 fuel inlet valve 166QM2 is open,
the ACT refuel valve 41QU is open,
the ACT transfer pump 1QH does not operate.

(11) ACT refuel (Ref. AMM D/O 28-25-00-00)

ACT Transfer System - FWD Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

The wing tanks and the center tank are refueled first, then the ACTs are refueled in the sequence that follows: ACT AFT1, ACT AFT2 and ACT FWD.
During the refuel:

ACT transfer valve 165QM is closed
ACT air shut-off valve 233QM is closed
ACT vent valve 234QM is open
Related ACT fuel-inlet valve 228QM* is open
FWD ACT isolation-valve 236QM is open
ACT refuel valve 41QU is open
ACT transfer pump 1QH does not operate.

(12) ACT refuel (Ref. AMM D/O 28-25-00-00)

ACT Transfer System - Center Tank - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - AFT Cargo Compartment - Block Diagram ** ON A/C NOT FOR ALL

The wing tanks and the center tank are refueled first, then the ACTs are refueled in the sequence that follows: ACT AFT1 and ACT AFT2.
During the refuel:

ACT transfer valve (165QM) is closed
ACT air-shut-off valve (233QM) is closed
ACT vent valve (234QM) is open
Related fuel inlet valve 228QM* is open
ACT refuel valve (41QU) is open
ACT fuel transfer-pump (1QH) does not operate.

** ON A/C NOT FOR ALL

6. Power Supply

ACT Transfer System - Schematic ** ON A/C NOT FOR ALL

** ON A/C NOT FOR ALL

7. Interface
The ACT transfer system has interfaces with:

21-31-00 Pressure Control and Monitoring System
28-11-00 Tanks
28-12-00 Tank Venting System
28-25-00 Refuel/Defuel System
28-42-00 Quantity Indicating
28-46-00 Tank Level Sensing
31-54-00 SDAC - Acquisition/Interface.

The ACT transfer system has interfaces with the:

Pressure Control and Monitoring System (Ref. AMM D/O 21-31-00-00)
Tanks (Ref. AMM D/O 28-11-00-00)
Tank Venting System (Ref. AMM D/O 28-12-00-00)
Refuel/Defuel System (Ref. AMM D/O 28-25-00-00)
Quantity Indicating (Ref. AMM D/O 28-42-00-00)
Tank Level Sensing (Ref. AMM D/O 28-46-00-00)
Auxiliary Fuel Management System (Ref. AMM D/O 28-51-00-00)
SDAC - Acquisition/Interface (Ref. AMM D/O 31-54-00-00).

** ON A/C NOT FOR ALL

8. Component Description

A. ACT Vent Valve

ACT Fuel Inlet Valve ** ON A/C NOT FOR ALL

The primary components of an ACT vent valve 167QM are:

a housing with attachment flange
a ball valve assembly (ball valve and spindle)
two end terminations.

Inside the housing a ball valve, mounted onto a spindle, is installed. The two end terminations are screwed into the housing. These end terminations are also used to connect the ACT vent shutoff valve to the vent system. The spindle connects the valve to an electrical actuator on the outside of the ACT.

The thermal relief device has valve and spring which are installed in the ball valve to release system pressure. Thermal expansion causes the system pressure to increase. When the thermal relief valve is closed, it operates from 4 psi (0.28 bar) to 7 psi (0.48 bar) to release pressure out of the ACT.

ACT Vent Valve (234QM) ** ON A/C NOT FOR ALL

The primary components of ACT vent-valve 234QM are:

A housing with an attachment flange
A drive shaft with a drive assembly
A ball valve assembly (ball valve and spindle)
Two end terminations.

The ball valve, a tached to a spindle, is installed in the housing. Two end terminations are turned into the housing. These end terminations are also used to connect the ACT vent shutoff-valve to the vent system. The valve is installed in the center tank and is connected by a drive shaft to the actuator on the top external surface of the center tank.

B. ACT Valve Actuators

Actuator - Fuel Inlet Valve/Vent Valve/Air Shut-off Valve ** ON A/C NOT FOR ALL

Each actuator has one electrical motor which turns the ball valve 90 deg. Limit switches in the actuator control the actuator movement and set the circuit for the next operation. With a position indicator at the end of the output shaft it is possible to see or feel the position of the actuator. The actuator flange is connected to the valve flange through a V-clamp.

Actuator - Fuel Inlet Valve/Vent Valve/Air Shut-off Valve ** ON A/C NOT FOR ALL

Each actuator has two electrical motors which turn the ball valve 90 deg. Limit switches in the actuator control the actuator movement and set the circuit for the next operation. With a position indicator at the end of the output shaft it is possible to see or feel the position of the actuator. The actuator flange is connected to the valve flange through a V-clamp.

C. ACT Fuel Inlet Valve

ACT Fuel Inlet Valve ** ON A/C NOT FOR ALL

The fuel inlet valve 166QM has the following major parts:

a housing with attachment flange
a ball valve assembly (ball valve and spindle)
two end terminations.

Inside the housing a ball valve, mounted onto a spindle, is installed. The two end terminations are screwed into the housing. These end terminations are also used to connect the ACT fuel inlet valve to the refuel transfer system. The spindle connects the valve to an electrical actuator on the outside of the ACT.

The thermal relief device has valve and spring which are installed in the ball valve to release system pressure. Thermal expansion causes the system pressure to increase. When the thermal relief valve is closed, it operates from 4 psi (0.28 bar) to 7 psi (0.48 bar) to release pressure out of the ACT.

ACT Fuel Inlet Valve ** ON A/C NOT FOR ALL

Each fuel inlet valve 228QM* has the following parts:

A housing with attachment flange
A ball valve assembly (ball valve and spindle)
Two end terminations.

A ball valve, attached to a spindle, is installed inside the housing. Two end terminations are turned into the housing. These end terminations are also used to connect the ACT fuel inlet valve to the refuel/transfer system. The spindle connects the valve to an electrical actuator on the outside of the ACT.

The thermal relief device has valve and spring which are installed in the ball valve to release system pressure. Thermal expansion causes the system pressure to increase. When the thermal relief valve is closed, it operates from 4 psi (0.28 bar) to 7 psi (0.48 bar) to release pressure out of the ACT.

D. Cabin Intake Air-Filter

Cabin Intake Air-Filter ** ON A/C NOT FOR ALL

Primary components of filter 183QM are:

An end plate
Two seals
A cartridge
A base plate.

The base plate has five studs. Four studs on one side of the base plate are used to connect the filter to the aircraft structure. The one stud on the other side of the base plate is used to assemble the cartridge, seals and end plate.

E. Check Valves

Check Valves ** ON A/C NOT FOR ALL

The check valves are installed in the pressurization line of the two ACT to prevent vapor from each ACT entering the cabin. With the check valves it is possible to pressurize the system from the ground test points.

(1) Check Valve (177QM)
The components of each check valve are:

a valve body,
a flap valve assembly,
a spring,
a hinge pin.

The valve assembly is attached to the valve body by a hinge pin. Forward pressure lifts the flap from its seating against the action of the spring. Absence of forward air pressure or a reverse flow causes the flap to close.

(2) In Line Check Valve (178QM, 179QM)
The in line check valve has these parts:

a valve seat assembly,
a valve body,
a tube nut.

The valve seat assembly has these parts:

a valve seat,
a flap valve assembly,
a hinge pin,
a spring.

The valve assembly is attached to the valve seat by a hinge pin. The assembled valve seat screws into valve body and is sealed with an O-ring. Forward pressure lifts the flap valve from its seating against the spring action. If there is no forward air pressure the spring closes and keeps the flap valve in the closed position. A reverse air flow causes the valve flap to close and prevents air/fuel vapor entering the cabin.

F. Check Valves

Check Valves ** ON A/C NOT FOR ALL

The check valves are installed in the pressurization line of ACT AFT1 and the ACT FWD to prevent vapour from each ACT entering the cabin. With the check valves it is possible to pressurize the system from the ground test points.

Check Valves ** ON A/C NOT FOR ALL

The check valve is installed in the pressurization line of ACT AFT1 to prevent vapour from each ACT entering the cabin. With the check valves it is possible to pressurize the system from the ground test points.

(1) Check Valve (231QM1 and 231QM4)

Check Valves ** ON A/C NOT FOR ALL

The components of each check valve are:

A valve body
A flap valve assembly
A spring
A hinge pin.

The valve assembly is attached to the valve body by a hinge pin. Pressure lifts the flap from its seating against the action of the spring. With no forward air pressure, a reverse flow causes the flap to close.

(2) In-Line Check Valve (178QM, 179QM)

Check Valves ** ON A/C NOT FOR ALL

The in-line check valve has these parts:

A valve seat assembly
A valve body
A tube nut.

The valve seat assembly has these parts:

A valve seat
A flap valve assembly
A hinge pin
A spring.

The valve assembly is attached to the valve seat by a hinge pin. The assembled valve seat turns into the valve body and is sealed with an O-ring. Pressure lifts the flap valve from its seating against the spring action. If there is no forward air pressure the spring closes and keeps the flap valve in the close position. A reverse air flow causes the valve flap to close and prevent that air/fuel vapor to enter into the cabin.

(3) Check Valve (231QM1)

Check Valves ** ON A/C NOT FOR ALL

The components of each check valve are:

A valve body
A flap valve assembly
A spring
A hinge pin.

(4) In-Line Check Valve (178QM, 179QM)

Check Valves ** ON A/C NOT FOR ALL

The in-line check valve has these parts:

A valve seat assembly
A valve body
A tube nut.

The valve seat assembly has these parts:

A valve seat
A flap valve assembly
A hinge pin
A spring.

G. ACT Air Shut-Off Valve

Air Shut-off Valve and Actuator ** ON A/C NOT FOR ALL

The air shutoff valve 168QM has these major components:

a housing assembly,
a ball valve assembly (ball valve and spindle),
two end-terminations.

In the housing a ball mounted onto a spindle is installed. Two end-terminations are connected to the housing by four bolts. Fitted to each termination end is a seal which contacts the surface of the ball.

The valve is electrically operated by an actuator which turns the ball 90 deg. to align the through passage in the ball with both valve ports.

Air Shut-off Valve and Actuator ** ON A/C NOT FOR ALL

The air shutoff-valve 233QM has these primary components:

A housing assembly
A ball valve assembly (ball valve and spindle)
Two end-terminations.

A ball attached to a spindle, is installed in the housing. Two end-terminations are connected to the housing by four bolts. A seal which contacts the surface of the ball is attached to each end-termination.

The valve is electrically operated by an actuator 90QH which turns the ball 90 deg. to align the through passage in the ball with each valve port.

H. Pressure Reducing Valve

Pressure Reducing Valve ** ON A/C NOT FOR ALL

The pressure reducing valve 171QM has four main parts:

a body group
a spring cover
an inlet union
an outlet union.

The body group is an assembly of the body, the control piston, the bleed screw and the poppet. The poppet and the control piston are attached to each other and secured by a clip. The outlet union and the inlet union is attached to the body group.
The spring is positioned between the control piston and the spring carrier. The spring carrier is screwed onto the vent union. On the sides of the spring carrier there are two flats which loosely engage with two flats in spring cover. In the bottom of the spring cover the vent union is installed together with an O-ring. The vent union loosely engages in two flats in the bottom of the spring cover. These flats prevent a rotation of the vent union when it is secured with a nut and a tab washer. The spring cover is screwed onto the body assembly, secured with a pin and sealed with an O-ring.

In the unpressurized condition the spring holds the poppet valve in the wide open position. Pressurized air entering the valve through the inlet union can pass to the outlet union through the open poppet valve. Air in the outlet union also passes through an axial and radial passage in the poppet valve and the radial passage of the piston into the chamber between piston and body. This causes a load on the piston in opposition to the spring load.
An increase of the outlet pressure will also increase the load on the piston and compress the spring until the poppet valve is closed. With the poppet valve closed the build-up of outlet pressure under zero flow conditions is prevented by a bleed hole in the poppet valve and the leakage through the clearance between piston and body. Inlet air which passes through the clearance between the poppet valve and body will flow through the bleed screw and the skirt of the body to the vent union. Usage of outlet air will cause a small pressure drop in the outlet union. This pressure drop will pass to the chamber between piston and body causing a decrease of the load on the piston. Because of the smaller load the compressed spring will open the poppet valve. The movement of the piston and poppet valve is stopped in a position where the spring force and the air pressure acting on the piston is equal. This is the position of the poppet valve which has been adjusted to keep a specified constant outlet-pressure and outlet flow. An adjustment of the outlet pressure is possible by changing the pre-load of the spring.

To adjust the pressure reducing valve (changing the spring pre-load) the vent union is pushed into the spring cover until the flats on the side of the vent union are disengaged. The spring carrier also has two flats which prevent a rotation when the vent union is turned. A rotation of the vent union moves the spring carrier axially and increases or decreases the spring pre-load. An anti-clockwise rotation increases and a clockwise rotation decreases the outlet pressure.

Pressure Reducing Valve ** ON A/C NOT FOR ALL

Pressure reducing valve 171QM has four main parts:

A body group
A spring cover
An inlet union
An outlet union.

The body group is an assembly of the body, the control piston, the bleed screw and the poppet. The poppet and the control piston are attached to each other and safetied by the clip. The outlet union and the inlet union are attached to the body group.
The spring is in position between the control piston and the spring carrier. The spring carrier is turned on the vent union. On the sides of the spring carrier there are two flats which loosely engage with two flats in the spring cover. The vent union is installed together with an O-ring in the bottom of the spring cover. The vent union loosely engages with two flats in the bottom of the spring cover. These flats prevent the vent union to turn when it is safetied with a nut and a tab washer. The spring cover is turned into the body assembly, safetied with a pin and sealed with an O-ring.

In the unpressurized condition the spring holds the poppet valve in the wide open position. When pressurized air goes into the valve inlet union it goes to the outlet union through the open poppet valve. Air in the outlet union also goes through an axial and radial passage in the poppet valve, and the radial passage of the piston into the chamber between piston and body. This causes a load on the piston in opposition to the spring load.

An increase of the outlet pressure also increases the load on the piston and compresses the spring until the poppet valve is closed. With the poppet valve closed the build-up of outlet pressure under zero flow conditions is prevented by a bleed hole in the poppet valve and the leakage through the clearance between piston and body. Inlet air which goes through the clearance between the poppet valve and body, flows through the bleed screw and the skirt of the body to the vent union. Leakage of outlet air causes a small pressure drop in the outlet union. This pressure drop goes to the chamber between piston and body, which causes a decrease of the load on the piston. Because of the smaller load the compressed spring opens the poppet valve. The movement of the piston and poppet valve is stopped in a position where the spring force and the air pressure on the piston is equal. This is the position of the poppet valve which was adjusted to keep a specified constant outlet-pressure and outlet flow. An adjustment of the outlet pressure is possible if you change the pre-load of the spring.

To adjust the pressure reducing valve (change the spring pre-load) the vent union is pushed into the spring cover until the flats on the side of the vent union are disengaged. Whent the vent union turns it moves the spring carrier axially and increases or decreases the spring pre-load. An anti-clockwise rotation increases and a clockwise rotation decreases the outlet pressure.

I. Refuel Restrictor Valve

ACT Refuel Restrictor Valve ** ON A/C NOT FOR ALL

The refuel restrictor valve 180QM has these major components:

a flange body half,
a coupling body half,
a restrictor plate,
a guide web.

The hinged restrictor plate is attached to the guide web with a hinge pin. On the opposite side to the hinge the restrictor plate has a slot which engages with the guide web. This web guides the restrictor plate through its whole range of travel and stops it in the free flow transfer position. The guide web assembly is installed in the flange body half. The coupling body half is attached to the flange body half with four bolts and nuts and sealed with an O-ring. Two slots in the coupling body half prevent a rotation of the guide web assembly.

During refuel of the ACT, the fuel enters the coupling body half and pushes the restrictor plate against a circular valve seat in the flange body half. The refuel flow is then limited by the size of the hole in the restrictor plate. Fuel flow in the opposite direction, forward fuel transfer, pushes the restrictor plate towards the coupling body half until it is at the stop of the guide web. In this position fuel flows freely over the raised restrictor plate and out of the coupling body half.

ACT Refuel Restrictor Valve ** ON A/C NOT FOR ALL

Refuel restrictor-valve 230QM* has these major components:

A flange body half
A coupling body half
A restrictor plate
A guide web.

The hinged restrictor plate is attached to the guide web with a hinge pin. On the opposite side to the hinge the restrictor plate has a slot which engages with the guide web. This web guides the restrictor plate through its whole range of travel and stops it in the free flow transfer position. The guide web assembly is installed in the flange body half. The coupling body half is attached to the flange body half with four bolts and nuts and sealed with an O-ring. Two slots in the coupling body half prevent a rotation of the guide web assembly.

During refuel of the ACT, the fuel enters the coupling body half and pushes the restrictor plate against a circular valve seat in the flange body half. The refuel flow is then limited by the size of the hole in the restrictor plate. Fuel flow in the opposite direction, pushes the restrictor plate to the coupling body half until it is at the stop of the guide web. In this position fuel flows freely above the raised restrictor plate and out of the coupling body half.

J. Transfer Pump

ACT Fuel Transfer Pump (1QH) ** ON A/C NOT FOR ALL

The ACT fuel transfer pump 1QH consists of:

a motor body and stator housing,
a shaft and rotor assembly,
a re-prime housing with re-prime impeller,
a labyrinth plate (flame-trap),
a main impeller assembly,
an inducer,
a pump housing,
a vapor pipe and flame-trap assembly.

The electrical driven fuel transfer pump is installed into a pump mounting plate. With integral mounting lugs on the pump housing, two pump attachment plates and four bolts, the transfer pump is attached to the pump mounting plate which is bolted to the inside of the aft wall of the center tank. The two attachment plates engage with the upper and lower mounting lugs on the pump housing. Through the holes in the attachment plates and in the aft tank wall, the bolts are screwed into the pump mounting plate. When the bolts are tighten, the pump and the pump mounting plate are pressed against the tank wall providing a safe and leak proof installation.

The pump housing has a fuel inlet, a fuel outlet and vapor discharge connections. In the pump housing the inducer/main impeller assembly, the re-prime impeller assembly, a flame-trap and a carbon bearing are installed.
The motor body has a 7 pin connector, a fuel sump and an outlet port for the vapor pipe. In the motor body the stator assembly, a carbon bearing, a rotor assembly and a re-prime suction pipe are installed.

The pump is driven by a fuel flooded 3 phase electrical motor. Each phase supply of the stator winding is protected by a thermal fuse which cannot be reset. When energized the motor turns the inducer, the main impeller assembly and the re-prime impeller. The inducer makes a suction that causes fuel to come through the inducer to the main impeller assembly. The main impeller pressurizes and pushes the fuel through the volute chamber to the fuel outlet.
Fuel is also circulated within the pump and motor housing to provide motor cooling, bearing lubrication and to create a suction at the main impeller. To prevent a de-priming of the pump, the re-prime pump removes fuel vapor and remaining air from the eye of the main impeller. The vapor is returned to the fuel tanks through the vapor pipe.
If the main impeller of an energized pump becomes deprimed, the re-prime pump will continue to draw fuel from the sump in the motor body. With this fuel the bearings are lubricated until the main impeller is able to deliver sufficient fuel flow.

ACT Fuel Transfer Pump (1QH) ** ON A/C NOT FOR ALL

ACT fuel-transfer pump 1QH has:

A motor body and stator housing
A shaft and rotor assembly
A primer housing with primer impeller
A labyrinth plate (flame trap)
A main impeller assembly
An inducer
A pump housing
A vapor pipe and flame trap assembly.

The electrically operated fuel transfer pump is installed on pump mounting plate 163QH. It is safetied with mounting lugs on the pump housing, two attachment plates and four bolts. The assembly is installed on the inner side of the aft wall of the center tank. Two attachment plates engage the upper and lower mounting lugs on the pump housing. The bolts are turned into the pump center tank. When the bolts are torqued, the pump and the pump mounting plate are pressed against the tank wall. This gives a safe and leak-proof are pushed against the tank wall. This gives a safe and leak-proof installation.

The pump housing has a fuel inlet, a fuel outlet and vapor discharge connections. The inducer/main impeller assembly, the primer impeller assembly, a flame trap and a carbon bearing are installed in the pump housing.

The motor body has a 7-pin connector, a fuel sump and an outlet port for the vapor pipe. A carbon bearing, a rotor assembly and a primer suction pipe are installed in the motor body and stator assembly.

A fuel-flooded 3-phase electrical motor supplies power to the pump. Each phase supply of the stator winding has protection by a thermal fuse which cannot be reset. When energized, the motor turns the inducer, the main impeller assembly and the primer impeller. The inducer makes a suction that causes fuel to come through the inducer to the main impeller assembly. The main impeller pressurizes and pushes the fuel through the volute chamber to the fuel outlet.

Fuel is also supplied in the pump and motor housing to supply motor cooling, bearing lubrication and to make a suction at the main impeller. To prevent a de-priming of the pump, the primer pump removes fuel vapor and remaining air from the eye of the main impeller. The vapor is goes back to the fuel tanks through the vapor pipe.
If the main impeller of an energized pump becomes de-primed, the primer pump continues to collect fuel from the sump in the motor body. This fuel lubricates the bearings until the main impeller can deliver sufficient fuel flow.

K. ACT Fuel Transfer Pump Mounting Plate

ACT Pump Mounting Plate ** ON A/C NOT FOR ALL

The pump mounting plate 163QM and attachment clamps are needed to install the fuel transfer pump to the aft wall of the center tank.

The major components of the pump mounting plate are:

the mounting plate body,
the fuel inlet, fuel outlet and vapor discharge adapters,
the fuel inlet, fuel outlet and vapor discharge non-return valves,
the inner sleeve of the vapor discharge hole,
the spider of the vapor discharge hole,
the inner sleeve of the fuel outlet hole.

The sleeve of the vapor hole has slots in which the spider is installed to permit an axial movement of the spider. The sleeves are installed in the vapor discharge and fuel outlet hole of the canister body. The fuel inlet and fuel outlet non-return valves are installed in their related adapters. The non-return valve and adapter of the vapor port, the fuel inlet adapter and the fuel outlet adaptor are mounted on the mounting plate body. A threaded port and drilling in the mounting plate body makes it possible to measure the fuel outlet pressure.

When the pump is installed in the pump canister a probe on the pump and the spider open the non-return valves in the fuel outlet and vapor discharge adapter. When the pump is removed from its mounting plate, the non-return valves close and prevents a fuel leakage from the center tank. The non-return valve of the fuel inlet port is opened by the fuel flow if the pump is operating. If the pump is not operating it closes and prevents a reverse fuel flow.

ACT Pump Mounting Plate ** ON A/C NOT FOR ALL

Pump mounting-plate 163QM and attachment clamps are necessary to install the fuel transfer pump to the aft wall of the center tank.

Primary components of the pump mounting plate are:

A mounting plate body
A fuel inlet, fuel outlet and a vapor discharge adapters
A fuel inlet, fuel outlet and a vapor discharge non-return-valves
An inner sleeve of a vapor discharge hole
A spider of a vapor discharge hole
An inner sleeve of a fuel outlet hole.

The sleeve of the vapor hole has slots in which the spider is installed to let an axial movement of the spider. The sleeves are installed in the vapor discharge and fuel outlet hole of the canister body. The fuel inlet and fuel outlet non-return-valves are installed in their related adapters. The non-return valve and adapter of the vapor port, the fuel inlet adapter and the fuel outlet adaptor are mounted on the mounting plate body. A threaded port and drilling in the mounting plate body makes it possible to measure the fuel outlet pressure.

When the pump is installed in the pump canister, a probe on the pump and the spider open the non-return valves in the fuel outlet and vapor discharge adapter. When the pump is removed from its mounting plate, the non-return valves close and prevent fuel leakage from the center tank. The non-return valve of the fuel inlet port is opened by the fuel flow if the pump is in operation. If the pump is not in operation it closes and prevents a reverse flow of fuel.

L. ACT Transfer Pump Pressure Switch

Pressure Switch (2QH) ** ON A/C NOT FOR ALL

The primary components of the pressure switch assembly 2QH, are the body and banjo adapter. The body contains:

a flexible diaphragm,
a switch mechanism,
an electrical micro switch.

The flexible diaphragm isolates the switch mechanism and the micro switch from the fuel. When the fuel pressure increases to 8 psi (0.55 bar) the flexible diaphragm moves to operate the switch mechanism. The switch mechanism then opens the contacts of the micro switch. When the fuel pressure decreases to 6 psi (0.41 bar) the flexible diaphragm and the switch mechanism move in the opposite direction. The switch mechanism then closes the contacts of the micro switch.

Pressure Switch (2QH) ** ON A/C NOT FOR ALL

The primary components of pressure-switch assembly 2QH, are the body and banjo adapter. The body contains:

A flexible diaphragm
A switch mechanism
An electrical micro switch.

The flexible diaphragm isolates the switch mechanism and the micro switch from the fuel. When the fuel pressure increases to 8 psi (0.55 bar) the flexible diaphragm moves to operate the switch mechanism. The switch mechanism then opens the contacts of the microswitch. When the fuel pressure decreases to 6 psi (0.41 bar) the flexible diaphragm and the switch mechanism moves in the opposite direction. The switch mechanism then closes the contacts of the micro switch.

M. ACT Transfer Valve

ACT Transfer Valve and Actuator ** ON A/C NOT FOR ALL

The ACT transfer valve 165QM has two sub-assemblies, a drive assembly and a valve assembly. The drive assembly interfaces the actuator and the valve assembly. The drive assembly is mounted through the aft wall of the center tank. The valve assembly is within the center tank.

The ball valve and the bottom spindle are installed in the valve body. The flange assembly is moved over the drive spindle and screwed to the valve body. The other side of the flange assembly is attached with four studs and two bolts to the aft wall of the center tank. It has an O-ring to prevent a leak of fuel through the mounting flange face. The two end retainers are attached to the valve body and provide mounting flanges to the transfer line. The four studs which attach the valve assembly are also used to attach the drive assembly to the center tank. The splined end of the drive spindle engages with a connector, which is installed in the drive assembly. A slot in the top of the connector engages with the drive shaft of the actuator.

ACT Transfer Valve and Actuator ** ON A/C NOT FOR ALL

ACT transfer-valve 165QM has a drive assembly and a valve assembly. The drive assembly interfaces the actuator and the valve assembly. The drive assembly is mounted through the aft wall of the center tank. The valve assembly is in the center tank.

The ball valve and the bottom spindle are installed in the valve body. The flange assembly is positioned along the drive spindle and attached to the valve body with screws. The other side of the flange assembly is attached with four studs and two bolts to the aft wall of the center tank. It has an O-ring to prevent a leak of fuel through the mounting flange face. The two end retainers are attached to the valve body and are used to provide mounting flanges to the transfer line. The four studs which attach the valve assembly are also used to attach the drive assembly to the center tank. The splined end of the drive spindle engages with a connector, which is installed in the drive assembly. A slot in the top of the connector engages with the drive shaft of the actuator.

N. ACT Transfer Valve Actuator

ACT Transfer Valve and Actuator ** ON A/C NOT FOR ALL

The actuator of the ACT transfer valve has two electrical motors which turn a ball valve through 90 deg. Limit switches in the actuator control this 90 deg movement and set the electrical circuit for the next operation. One of the two motors can open or close the valve if the other motor is damaged. A V-band clamp attaches the actuator to the flange of the drive assembly. A location peg makes sure that the actuator engages correctly.

ACT Transfer Valve and Actuator ** ON A/C NOT FOR ALL

The actuator of the ACT transfer valve has two electrical motors which turn a ball valve through 90 deg. Limit switches in the actuator control this 90 deg. movement and set the electrical circuit for the next operation. One of the two motors can open or close the valve if the other motor is damaged. A V-band clamp attaches the actuator to the flange of the drive assembly. A location peg makes sure that the actuator engages correctly.

O. Check Valve

Fuel Transfer Check Valve ** ON A/C NOT FOR ALL

The check valve 176QM has the subsequent components:

an inlet body,
an outlet body,
a valve assembly,
a spring.

In the outlet body the valve assembly and a spring are installed with a pivot pin. The inlet body contains a valve seat which can be sealed with the valve assembly. The valve assembly is pushed against the valve seat by the spring. The two bodies are held together with a trap-wire and sealed with an O-ring.

When the inlet pressure is greater than the load of the spring, the valve assembly lifts from the valve seat in the inlet body. Fuel then flows through the check valve. If the fuel pressure on both sides of the valve assembly is equal, the spring returns the valve to its seat. This stops the flow of fuel. If the outlet pressure increases, the valve assembly is pushed on to the valve seat. This prevents a fuel flow to the inlet side of the check valve.

Fuel Transfer Check Valve ** ON A/C NOT FOR ALL

Check valves 176QM, 239QM and 240QM have the subsequent components:

An inlet body
An outlet body
A valve assembly
A spring.

The valve assembly and a spring are installed in the outlet body with a pivot pin. The inlet body contains a valve seat which is sealed with the valve assembly. The valve assembly is pushed against the valve seat by the spring. The two bodies are held together with a trap-wire and sealed with an O-ring.

When the inlet pressure is more than the load of the spring, the valve assembly lifts from the valve seat in the inlet body. Fuel then flows through the check valve. If the fuel pressure on both sides of the valve assembly is equal, the spring goes back to the valve to its seat. This stops the flow of fuel. If the outlet pressure increases, the valve assembly pushes the valve seat. This prevents a flow of fuel to the inlet side of the check valve.

Fuel Transfer Check Valve ** ON A/C NOT FOR ALL

Check valves 176QM and 239QM have the subsequent components:

An inlet body
An outlet body
A valve assembly
A spring.

The valve assembly and a spring are installed in the outlet body with a pivot pin. The inlet body contains a valve seat which is sealed with the valve assembly. The valve assembly is pushed against the valve seat by the spring. The two bodies are held together with a trap-wire and sealed with an O-ring.
When the inlet pressure is more than the load of the spring, the valve assembly lifts from the valve seat in the inlet body. Fuel then flows through the check valve. If the fuel pressure on both sides of the valve assembly is equal, the spring goes back to the valve to its seat. This stops the flow of fuel. If the outlet pressure increases, the valve assembly pushes the valve seat. This prevents a flow of fuel to the inlet side of the check valve.

P. Leak Monitor

Leak Monitor ** ON A/C NOT FOR ALL

The primary components of the leak monitors 184QM and 185QM are:

the body with a mounting flange,
a remote inlet,
an outer valve and spring,
an inner valve and spring,
a support guide.

The mounting flange connects the valve to the aircraft. The body has an inner and outer valve and the springs. The inner valve is installed in the outer valve and the springs keep the two valves in the closed position. The support guide keeps the two valves aligned when they operate. The remote inlet of 184QM connected to the shrouded ACT refuel/transfer and ACT vent pipes. The remote inlet of 185QM is connected to the interspaces.

When a drain tool opens the outer valve, the inner valve opens at the same time. Then fuel or water can flow out through the valve. If the outer valve is closed the inner valve also closes. When the outer valve is removed the inner valve stays closed and prevents a fuel leakage.

Leak Monitor ** ON A/C NOT FOR ALL

The primary components of leak monitors 253QM, 254QM and 255QM are:

A body with a mounting flange
A remote inlet
An outer valve and spring
An inner valve and spring
A support guide.

The mounting flange connects the valve to the aircraft. The body has an inner and outer valve and the springs. The inner valve is installed in the outer valve and the springs keep the two valves in the close position. The support guide keeps the two valves aligned when they operate. The remote inlet is connected to the shrouded ACT refuel/transfer and ACT vent pipes.

When a drain tool opens the outer valve, the inner valve opens at the same time. Then fuel or water can flow out through the valve. If the outer valve is closed the inner valve also closes. When the outer valve is removed the inner valve stays closed and prevents a fuel leakage.

Leak Monitor ** ON A/C NOT FOR ALL

The primary components of leak monitors 254QM and 255QM are:

A body with a mounting flange
A remote inlet
An outer valve and spring
An inner valve and spring
A support guide.

The mounting flange connects the valve to the aircraft. The body has an inner and outer valve and the springs. The inner valve is installed in the outer valve and the springs keep the two valves in the close position. The support guide keeps the two valves aligned when they operate. The remote inlet is connected to the shrouded ACT refuel/transfer and ACT vent pipes.
When a drain tool opens the outer valve, the inner valve opens at the same time. Then fuel or water can flow out through the valve. If the outer valve is closed the inner valve also closes. When the outer valve is removed the inner valve stays closed and prevents a fuel leakage.

Q. ACT Thermal Relief Valve

ACT Transfer Thermal Relief Valve ** ON A/C NOT FOR ALL

The valve body contains a ball and a spring. The spring holds the ball against a valve seat. When the fuel pressure increases to more than 2.75 bar (40 psi) the ball lifts (against the pressure of the spring) to release the fuel through the outlet holes.

R. ACT Thermal Relief Valves 237QM and 238QM

ACT Transfer Thermal Relief Valve ** ON A/C NOT FOR ALL

S. ACT Pressure Holding Valve (241QM, 242QM, 243QM)

Pressure Holding Valve ** ON A/C NOT FOR ALL

The valve body contains a ball and a spring. The spring holds the ball against a valve seat. When the air pressure increases to more than 0.664 bar (9.6305 psi), the valve opens and releases the pressure into the vent line.

T. Forward ACT Isolation Valve (236QM) and the Actuator (92QH)

Forward ACT Isolation Valve (236QM) and the Actuator (92QH) ** ON A/C NOT FOR ALL

The ACT isolation valve has a drive assembly and a valve assembly. The drive assembly interfaces the actuator and the valve assembly. The drive assembly is installed through the aft wall of the center tank. The valve assembly is installed in the refuel gallery. When the valve is closed, the ACT(s) installed in the forward cargo compartment are isolated from the refuel/defuel system.

The ball valve and the bottom spindle are installed in the valve body. The flange assembly is positioned along the drive spindle and attached to the valve body with screws. The other side of the flange assembly is attached with four studs and two bolts to the aft wall of the center tank. It has an O-ring to prevent leak of fuel through the mounting flange face. The four studs which attach the valve assembly are also used to attach the drive assembly to the center tank. The splined end of the drive spindle engages with a connector installed in the drive assembly. A slot in the top of the connector engages with the drive shaft of the actuator.

The actuator of the ACT isolation valve has two electrical motors which turn a ball valve through 90 deg. Limit switches in the actuator control this 90 deg. movement and set the electrical circuit for the next operation. If the ACT(s) in the forward cargo compartment is(are) not installed, the valve will stay closed and power will not go to the two electrical motors. A V-band clamp attaches the actuator to the flange of the drive assembly. A location peg makes sure that the actuator engages correctly.

U. Ground Fault Interrupter (122QH, 124QH)

GFI - Component Location ** ON A/C NOT FOR ALL

The primary components of the Ground Fault Interrupter (GFI) are:

A 3 pole single throw relay and
An auxiliary single pole double throw contact.

Operational functions of the GFI are as follows:

If a ground fault occurs in the load or on the wiring, downstream of the GFI:
The GFI micro-contactor will operate to isolate the load and ground fault from the power supply
The GFI will trip and the RESET P/BSW metallic shaft will come into view.

The GFI will operate to close the main contacts when the load is set to ON (relay coil supplied with 28 VDC or 100 VDC). When the load is set to OFF, the main contacts of the GFI will open.
When the RESET P/BSW is in the normal position, the RESET P/BSW metallic shaft will not come into view.

The GFI micro-contactor can be tripped when the AUTO-TEST P/BSW is pushed. If the RESET P/BSW is in the normal position, the function of the GFI is defective. The GFI micro-contactor can be unlatched when the RESET P/BSW is pushed. Pin connections A1 and C1 must be energized to do the auto-test of the GFI.

The GFI will trip when the:
Maximum differential current is between 1.35 A and 1.65 A
Detection time of the GFI is between 2.9 and 3.1 milliseconds
Total reaction time of the GFI (detection time and the opening time of the contactor to isolate the system) is more than 20 milliseconds.

** ON A/C NOT FOR ALL

9. Operation/Control and Indicating

ACT Transfer System - Component Location ** ON A/C NOT FOR ALL

ACT Transfer System - Block Diagram ** ON A/C NOT FOR ALL

** ON A/C NOT FOR ALL

10. Operation/Control and Indicating

ACT Transfer System - Component Location ** ON A/C NOT FOR ALL

ACT Transfer System - Block Diagram ** ON A/C NOT FOR ALL

ACT Transfer System - Schematic ** ON A/C NOT FOR ALL

Lower ECAM Display Unit - Fuel Page ** ON A/C NOT FOR ALL

** ON A/C NOT FOR ALL

11. Operation/Control and Indicating

Cockpit Overhead Fuel Panel ** ON A/C NOT FOR ALL

ECAM Fuel Page ** ON A/C NOT FOR ALL

** ON A/C NOT FOR ALL

12. Operation/Control and Indicating

A. ACT Refuel (Ref. 28-25-00)
When ACT refuel is selected, the refuel transfer system commands the ACT refuel valve (41QU) and the ACT1 fuel inlet valve (166QM1) to the open position. All aircraft tanks are refueled at the same time. The high level sensor of the ACT provide a signal to the system when the ACT is full with fuel, to close the ACT fuel inlet valve (166QM1), and to stop the refuel of the ACT (Ref. AMM D/O 28-25-00-00).

B. ACT Refuel
When ACT refuel is selected on the refuel/defuel panel, the refuel transfer system commands the ACT refuel valve (41QU), and the ACT1 and ACT2 fuel inlet valves (166QM1 and 166QM2) to the open position. All aircraft tanks are refueled at the same time. The high level sensors of the ACT(s) provide a signal to the system when all the ACT(s) are full with fuel, to close the related ACT fuel inlet valve (166QM1, 166QM2), and to stop the refuel of the ACT(s) (Ref. AMM D/O 28-25-00-00).

C. ACT(s) Refueling (Ref. 28-25-00)
Refueling of the ACT can be automatic or manual:

(1) Automatic Refueling
For the automatic refueling of the ACT(s), you must have these conditions:

At least one ACT inlet valve open
The transfer valve closed
The air shut-off valve closed
The vent valve open
The forward ACT vent isolation-valve open (if the ACT in the forward cargo compartment will be refueled)
The forward ACT isolation-valve open (if the ACT in the forward cargo compartment will be refueled).

When all the ACT REFUEL VALVE switch(es) are set to NORM, automatic refuel can occur.
The AFMC calculates which of the ACT (in the sequence that follows: ACT AFT1, ACT AFT2, ACT FWD) needs to be refueled. This will be with reference to the flight duration. All ACT which need fuel are refueled at the same time, but not the highest numbered ACT. The highest numbered ACT is controlled by the AFMC to get the correct quantity of fuel.

(2) Manual Refueling
The conditions for manual refuel are the same as those for automatic refuel. It is possible to refuel a combination of ACT, independently or at the same time, when the ACT REFUEL VALVE switch(es) of the combination is (are) not set to NORM. Refuel starts when the relevant ACT REFUEL VALVE switch is set to OPEN. Refuel stops when the ACT high level sensor becomes wet or the switch is moved from OPEN.

(3) Automatic Refueling
For the automatic refueling of the ACT(s), you must have these conditions:

At least one ACT inlet valve open
The transfer valve closed
The air shut-off valve closed
The vent valve open

When all the ACT REFUEL VALVE switch(es) are set to NORM, automatic refuel can occur.
The AFMC calculates which of the ACT (in the sequence that follows: ACT AFT1 and ACT AFT2) needs to be refueled. This will be with reference to the flight duration. All ACT which need fuel are refueled at the same time, but not the highest numbered ACT. The highest numbered ACT is controlled by the AFMC to get the correct quantity of fuel.

(4) Manual Refueling
The conditions for manual refuel are the same as those for automatic refuel. It is possible to refuel a combination of ACT, independently or at the same time, when the ACT REFUEL VALVE switch(es) of the combination is (are) not set to NORM. Refuel starts when the relevant ACT REFUEL VALVE switch is set to OPEN. Refuel stops when the ACT high level sensor becomes wet or the switch is moved from OPEN.

D. Automatic Forward Transfer
For the automatic forward transfer to occur, you must have these conditions:

the aircraft is in flight,
the ACT pushbutton switch is in the AUTO position (on the overhead FUEL panel 40VU)
at least one ACT low level sensor is wet,
the center tank hi-level sensor has been dry for at least 10 minutes.

When these conditions occur, the control circuit:

closes the vent valve
opens the air shutoff valve
opens the fuel transfer valve
opens the fuel inlet valve.

The air pressure in the cargo compartment transfers the fuel from the ACT to the center tank.

If the center tank hi-level sensor becomes wet during a forward fuel transfer, the Tank Level Sensing system and the control circuit closes the ACT fuel transfer valve and the ACT fuel inlet valve. The fuel transfer stops. When the center tank hi-level sensor becomes dry, the Tank Level Sensing system and the control circuit (after a 10 minutes delay) open the ACT fuel transfer valve and the ACT fuel inlet valve. The fuel transfer starts again.

When the ACT low level sensors become dry, the control circuit:

closes the fuel transfer valve
closes the ACT fuel inlet valve.

The fuel transfer from the ACT to the center tank stops.

E. Automatic Forward Fuel Transfer
For the automatic forward transfer to occur, you must have these conditions:

the aircraft is in flight,
the ACT pushbutton switch is in the AUTO position (on the overhead FUEL panel 40VU)
the ACT2 low level sensor is wet,
the center tank hi-level sensor has been dry for at least 10 minutes.

When these conditions occur, the control circuit:

closes the ACT1 and ACT2 vent valve,
opens the air shutoff valve,
opens the fuel transfer valve,
opens the ACT2 fuel inlet valve.

The air pressure in the cargo compartment transfers the fuel from the ACT2 to the center tank.

If the center tank hi-level sensor becomes wet during a forward fuel transfer, the Tank Level Sensing system and the control circuit close the ACT fuel transfer valve and the ACT2 fuel inlet valve. The fuel transfer stops. When the center tank hi-level sensor becomes dry, the Tank Level Sensing system and the control circuit (after a 10 minutes delay) opens the ACT fuel transfer valve and the ACT2 fuel inlet valve. The fuel transfer starts again.

When the ACT2 low level sensors become dry, the control circuit:

closes the ACT2 fuel inlet valve,
opens the ACT1 fuel inlet valve.

The fuel is now transferred from the ACT1 to the center tank.

When the ACT1 low level sensors become dry, the control circuit:

closes the fuel transfer valve,
closes the ACT1 fuel inlet valve,

The fuel transfer from the ACT to the center tank stops.

F. ACT Automatic Fuel Transfer
For automatic transfer, you must have these conditions:

The aircraft is in flight with the landing gear retracted (when the aircraft is in flight, the AFMC opens the air shut-off valve and closes the vent valve)
There is fuel in one or more ACT (low level sensors are wet)
The forward ACT isolation-valve must be open, to start the fuel transfer from the ACT in the forward cargo-compartment to the center tank
The fuel quantity in the center tank is below 5000 kg (11023 lb)
The aircraft altitude is above approximately 8000 ft, for ACT pressurization to occur.

When these conditions occur and approximately 30 minutes after the start of the pressurization of the ACT(s), the control circuit:

Opens the ACT transfer valve
Opens the fuel inlet valve of the highest numbered ACT which contains fuel.

The ACT fuel-transfer pump controls and energizes the Ground Fault Interrupter (GFIs) (122QH and 124QH). The GFIs send signal to the ACT fuel-transfer pump to operate it independently.

The air pressure in the cargo-compartment transfers the fuel from the ACT(s) to the center tank for a minimum of 60 seconds, or until the first ACT is empty of fuel for a minimum of 60 seconds.
If the fuel quantity in the center tank increases up to 5750 kg (12677 lb), the fuel transfer from the ACT stops until the fuel quantity in the center tank is below 5000 kg (11023 lb). After that, the fuel transfer to the center tank starts again.
When the low level sensors of the ACT becomes dry, and the fuel quantity in the applicable ACT is zero, the control circuit:

Closes the fuel inlet valve of the applicable ACT
Opens the inlet valve of the next ACT which contains fuel.

The fuel transfer to the center tank goes on with the next applicable ACT.
This process continues until all ACTs are empty. The control circuit:

Closes the ACT transfer valve
Closes the inlet valves of all the ACTs in the applicable sequence ACT FWD, ACT AFT2 and ACT AFT1.

The fuel transfer from the ACT to the center tank stops.

When the aircraft is landing, the AFMC opens the vent valve and closes the air shut-off valve.

For automatic transfer, you must have these conditions:

The aircraft is in flight with the landing gear retracted (when the aircraft is in flight, the AFMC opens the air shut-off valve and closes the vent valve)
There is fuel in one or more ACT (low level sensors are wet)
The fuel quantity in the center tank is below 5000 kg (11023 lb)
The aircraft altitude is above approximately 8000 ft, for ACT pressurization to occur.

When these conditions occur and approximately 30 minutes after the start of the pressurization of the ACT(s), the control circuit:

Opens the ACT transfer valve
Opens the fuel inlet valve of the highest numbered ACT which contains fuel.

The ACT fuel-transfer pump controls and energizes the Ground Fault Interrupter (GFIs) (122QH and 124QH). The GFIs send signal to the ACT fuel-transfer pump to operate it independently.
The air pressure in the cargo-compartment transfers the fuel from the ACT(s) to the center tank for a minimum of 60 seconds, or until the first ACT is empty of fuel for a minimum of 60 seconds.
If the fuel quantity in the center tank increases up to 5750 kg (12677 lb), the fuel transfer from the ACT stops until the fuel quantity in the center tank is below 5000 kg (11023 lb). After that, the fuel transfer to the center tank starts again.
When the low level sensors of the ACT becomes dry, and the fuel quantity in the applicable ACT is zero, the control circuit:

Closes the fuel inlet valve of the applicable ACT
Opens the inlet valve of the next ACT which contains fuel.

The fuel transfer to the center tank goes on with the next applicable ACT.
This process continues until all ACTs are empty. The control circuit:

Closes the ACT transfer valve
Closes the inlet valves of all the ACTs in the applicable sequence ACT AFT2 and ACT AFT1.

The fuel transfer from the ACT to the center tank stops.
When the aircraft is landing, the AFMC opens the vent valve and closes the air shut-off valve.

G. Manual Forward Fuel Transfer
For a manual forward fuel transfer on the ground, you must do:

open the applicable refuel panel 192MB or 522KB or 622KB,
push the ACT pushbutton switch in the cockpit (the FWD legend comes on).
When the ACT pushbutton switch is pushed, the electrical control circuit:
opens the ACT fuel transfer valve,
opens the ACT fuel inlet valve,
energizes the ACT transfer pump.

It transfers the fuel from the ACT to the center tank.

If the ACT pump pressure switch detects a low pressure (and the ACT is empty if the aircraft is in flight) the FUEL - ACT PUMP LO PR warning appears on the upper ECAM display unit and on the overhead fuel panel. When the ACT pushbutton switch is released (the FWD legend goes off) the control circuit:

closes the ACT fuel transfer valve,
closes the ACT fuel inlet valve,
de-energizes the ACT transfer pump.

Thus the fuel transfer from the ACT to the center tank is stopped.

H. Manual Forward Fuel Transfer
For a manual forward fuel transfer on the ground, you must do:

open the applicable refuel panel 192MB or 522KB or 622KB,
push the ACT pushbutton switch in the cockpit (the FWD legend comes on).
The fuel transfer sequence is ACT2 first and then ACT1.
When the ACT pushbutton switch is pushed, the electrical control circuit:
opens the ACT fuel transfer valve,
opens the ACT2 fuel inlet valve,
energizes the ACT transfer pump.

It transfers the fuel from the ACT2 to the center tank.

If the ACT1 and ACT2 are empty, the ACT pump pressure switch detects a low pressure and the FUEL - ACT PUMP LO PR warning appears on the upper ECAM display unit. The fault light illuminate in the ACT pushbutton on the overhead fuel panel. When the ACT pushbutton switch is released (the FWD legend goes off) the control circuit:

closes the ACT fuel transfer valve,
closes the ACT1 and ACT2 fuel inlet valve,
de-energizes the ACT transfer pump.

Thus the fuel transfer from the ACT1 and ACT2 to the center tank is stopped.

I. ACT Manual Fuel Transfer

Cockpit Overhead Fuel Panel ** ON A/C NOT FOR ALL

For a manual transfer to occur, you must push the ACT XFR MODE SEL pushbutton switch (the MAN legend comes on). The normal fuel transfer sequence is ACT FWD, ACT AFT2 and ACT AFT1.
When the ACT XFR MODE SEL pushbutton switch is pushed, and the rotary switch is set to the OFF position, the electrical control circuit:

Opens the ACT transfer valve
Closes all the ACT fuel inlet valves.

A two-seconds time delay is used to prevent movement of valves when the rotary switch is turned through the ACT positions.
With the aircraft on the ground, the inlet valve of that ACT opens when the rotary switch is turned to an ACT position. The ACT transfer valve opens and the ACT fuel transfer pump starts to operate when the pushbutton switch for manual mode is pushed and engaged. Transfer is inhibited if the center tank high level sensor is wet, which keeps the ACT transfer valve closed.
With the aircraft in flight, the inlet valve of that ACT opens when the rotary switch is turned to an ACT position. The ACT transfer valve opens no matter how much fuel is in the center tank. The ACT fuel transfer pump starts to operate when the pushbutton switch for manual mode is pushed and engaged.
With the aircraft on the ground or in flight, the air shut-off valve opens and the vent valve closes. The position of the rotary switch has no effect on this condition.

When the ACT XFR MODE SEL pushbutton switch is released (the MAN legend goes off) and the control circuit:

Puts the ACT fuel inlet valves back to AFMC control
De-energizes the ACT fuel transfer pump
Closes the ACT transfer valve
Opens the vent valve (if the aircraft is on the ground)
Closes the air shut-off valve (if the aircraft is on the ground)
Puts the fuel transfer back to the auto mode.

Fuel transfer now stops.

Cockpit Overhead Fuel Panel ** ON A/C NOT FOR ALL

For a manual transfer to occur, you must push the ACT XFR MODE SEL pushbutton switch (the MAN legend comes on). The normal fuel transfer sequence is ACT AFT2 and ACT AFT1.
When the ACT XFR MODE SEL pushbutton switch is pushed, and the rotary switch is set to the OFF position, the electrical control circuit:

Opens the ACT transfer valve
Closes all the ACT fuel inlet valves.

Puts the ACT fuel inlet valves back to AFMC control
De-energizes the ACT fuel transfer pump
Closes the ACT transfer valve
Opens the vent valve (if the aircraft is on the ground)
Closes the air shut-off valve (if the aircraft is on the ground)
Puts the fuel transfer back to the auto mode.

Fuel transfer now stops.

J. Operation with Failure

(1) Failure of the Automatic Transfer
The FQIC signals a transfer fault if in the center tank there is less than 3000Kg (6614lb) of usable fuel and in the ACT there is more than 250Kg (550lb) fuel available , then:

the EWD shows the warning FUEL - ACT XFR FAULT on the upper ECAM display unit
the FAULT legend in the ACT pushbutton switch comes on.

(2) Failure of the ACT Transfer Pump
If the ACT transfer pump is selected to run and the ACT transfer-pump pressure-switch 2QH detects a low pressure:

the EWD shows the warning FUEL - ACT PUMP LO PR,
the FAULT legend in the ACT pushbutton switch comes on.

In flight, the warning caption illumination is inhibited until at least one of the low level sensors in the ACT indicates "dry".

K. Operation with Failure

(1) Failure of the Automatic Transfer
The FQIC signals a transfer fault if in the center tank there is less than 3000Kg (6614lb) of usable fuel and if one ACT has more than 250Kg (550lb) of fuel available, then:

the EWD shows the warning FUEL - ACT XFR FAULT on the upper ECAM display unit
the FAULT legend in the ACT pushbutton switch comes on.

(2) Failure of the ACT Transfer Pump
If the ACT transfer pump is selected to run and the ACT transfer-pump pressure-switch 2QH detects a low pressure:

the EWD shows the warning FUEL - ACT PUMP LO PR,
the FAULT legend in the ACT pushbutton switch comes on.

In flight, the warning caption illumination is inhibited until at least one of the low level sensors in the ACT indicates "dry".

L. Operation with Failure

(1) Failure of the automatic transfer:

(a) The FQIC gives a signal of a transfer fault if:

1 There is less than 3000 kg (6614 lb) of fuel which you can use in the center tank and one ACT has more than 250 kg (551 lb) of fuel:

The EWD shows the warning "FUEL - ACT XFR FAULT" on the upper ECAM display unit
The FAULT legend on the ACT XFR MODE SEL pushbutton switch comes on.

(2) Failure of the ACT fuel transfer pump:

(a) If the ACT transfer pump is selected to run, the selected ACT is empty, and the ACT transfer-pump pressure-switch 2QH detects a low pressure for more than 60 seconds:

The EWD shows the warning "FUEL - ACT PUMP LO PR".

[Rev.10 from 2021] 2026.04.02 06:17:46 UTC