DOC AIRBUS | AMM A320FCARGO COMPARTMENT VENTILATION - DESCRIPTION AND OPERATION
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1. General
A. Cargo-Compartment Ventilation
The FWD cargo-compartment ventilation-system supplies air to the FWD cargo compartment. The ventilation air comes from the cabin zones through openings in the cabin floor behind the sidewall panels.
The AFT cargo-compartment ventilation-system, supplies air to the AFT cargo compartment. The ventilation air comes from the cabin zones through openings in the cabin floor behind the sidewall panels.
The FWD cargo-compartment ventilation-system supplies air to the FWD cargo compartment. The ventilation air comes from the cabin zones through openings in the cabin floor behind the sidewall panels.
The AFT cargo-compartment ventilation-system, supplies air to the AFT cargo compartment. The ventilation air comes from the cabin zones through openings in the cabin floor behind the sidewall panels.
2. Component Location
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
FWD Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
FWD Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL FWD Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL FWD Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL | FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
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| 4HN | ISOL VALVE FWD CARGO OUTLET | 132KW | 132 | 21-28-51 | |
| 5HN | ISOL VALVE FWD CARGO INLET | 131MW | 131 | 21-28-51 | |
| 6HN | FWD CARGO FAN | 132KW | 132 | 21-28-53 | |
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| 10HN | CARGO VENT CONTROLLER | 103VU | 126 | 21-28-34 | |
| ** ON A/C NOT FOR ALL | |||||
| 21HN | DIFFERENTIAL PRESS SWITCH | 132KW | 132 | 21-28-11 | |
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| 33HN | ISOL VALVE AFT CARGO OUTLET | 162DW | 172 | 21-28-52 | |
| 34HN | ISOL VALVE AFT CARGO INLET | 151EW | 151 | 21-28-52 | |
| 35HN | AFT CARGO FAN | 162DW | 172 | 21-28-54 | |
3. System Description
AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL
FWD Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL
Cargo-Compartment Ventilation-System
Suction from the extraction fan 35HN causes air to flow into the ventilation system of the AFT cargo compartment when the extraction fan 35HN operates on the ground or in flight. Three inlets installed along the compartment lower left-hand sidewall, direct the air towards the compartment floor area. An isolation valve 34HN is installed in distribution ducts upstream of the compartment inlets.
The AFT compartment air is extracted through two outlets near the compartment ceiling on the aft end wall. The air goes through the extraction fan 35HN and an isolation valve 33HN and is discharged in the area of the outflow valve 10HL.
FWD Cargo-Compartment Ventilation-System
Suction in the FWD cargo compartment pulls cabin air into the compartment through ducts routed along the lower fuselage interior. The suction is caused from the extraction fan 6HN or through differential pressure in flight. Seven inlets installed along the compartment lower left-hand sidewall, direct the air towards the compartment floor area. An isolation valve 5HN is installed in the distribution ducts upstream of the compartment inlets.
The FWD cargo compartment air is extracted through an outlet near the compartment ceiling (located between frames 28 and 29) on the right-hand sidewall. The air goes through an extraction fan 6HN, an isolation valve 4HN and then overboard through a venturi located in the aircraft skin. The extraction fan operates on ground and in flight, when the differential pressure switch 21HN detects a differential pressure which is below 1 psi.
The flowrate through the AFT cargo compartment is:
The flowrate through the FWD cargo compartment is:
** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL FWD Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL Suction from the extraction fan 35HN causes air to flow into the ventilation system of the AFT cargo compartment when the extraction fan 35HN operates on the ground or in flight. Three inlets installed along the compartment lower left-hand sidewall, direct the air towards the compartment floor area. An isolation valve 34HN is installed in distribution ducts upstream of the compartment inlets.
The AFT compartment air is extracted through two outlets near the compartment ceiling on the aft end wall. The air goes through the extraction fan 35HN and an isolation valve 33HN and is discharged in the area of the outflow valve 10HL.
FWD Cargo-Compartment Ventilation-System
Suction in the FWD cargo compartment pulls cabin air into the compartment through ducts routed along the lower fuselage interior. The suction is caused from the extraction fan 6HN or through differential pressure in flight. Seven inlets installed along the compartment lower left-hand sidewall, direct the air towards the compartment floor area. An isolation valve 5HN is installed in the distribution ducts upstream of the compartment inlets.
The FWD cargo compartment air is extracted through an outlet near the compartment ceiling (located between frames 28 and 29) on the right-hand sidewall. The air goes through an extraction fan 6HN, an isolation valve 4HN and then overboard through a venturi located in the aircraft skin. The extraction fan operates on ground and in flight, when the differential pressure switch 21HN detects a differential pressure which is below 1 psi.
The flowrate through the AFT cargo compartment is:
| Volumetric Airflow Mass Flow |
| - ground 160 l/s 190 g/s, |
| - flight 160 l/s 141 g/s. |
The flowrate through the FWD cargo compartment is:
| Volumetric Airflow Mass Flow |
| - ground 118 l/s 140 g/s, |
| - flight 165 l/s 145 g/s. |
4. Power Supply
AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation - Electrical Schematic ** ON A/C NOT FOR ALL 5. Component Description
A. Cargo Ventilation Controller FIN: 10-HN
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
The cargo ventilation controller 10HN is of a modular construction and consists of:
The cargo ventilation controller 10HN is of a modular construction and consists of:
The cargo ventilation controller 10HN is of a modular construction and consists of:
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL - a chassis,
- a common power supply module,
- a FWD cargo ventilation module,
- a FWD cargo power relay,
- an AFT cargo ventilation module,
- an AFT cargo power relay,
- a spare module connector,
- a spare power relay socket.
The cargo ventilation controller 10HN is of a modular construction and consists of:
- a chassis,
- a common power supply module,
- a FWD cargo ventilation module,
- a FWD cargo power relay,
- an AFT cargo ventilation module,
- an AFT cargo power relay,
- a spare module connector,
- a spare power relay socket.
The cargo ventilation controller 10HN is of a modular construction and consists of:
- a chassis,
- a common power supply module,
- a FWD cargo ventilation module,
- a FWD cargo power relay,
- an AFT cargo ventilation module,
- an AFT cargo power relay,
- a spare module connector,
- a spare power relay socket.
B. Isolation Valves
The FWD cargo compartment isolation valves 4HN and 5HN are electrically operated butterfly valves. Each valve has a body assembly and an actuator housing which are bolted together and internally connected. The actuator housing contains a gear-train, two microswitches, a 28 VDC motor and an electrical connector. The 28 VDC motor drives the gear-train, which turns the butterfly valve through a shaft. Two microswitches senses the fully open/fully closed position of the isolation valve and give a signal to the cargo ventilation controller 10HN.
Accidental blockage of either isolation valve will cause a torque-limit mechanism to disengage the gear-train. This protects the gear-train and butterfly valve from damage. A manual override and visual position indicator is connected to the end of the shaft at the top of the actuator.
The AFT cargo compartment isolation valves 33HN and 34HN are electrically operated butterfly valves. Each consists of a body assembly and an actuator housing which are bolted together and internally connected. The actuator housing contains a gear-train, two microswitches, a 28 VDC motor and an electrical connector. The 28 VDC motor drives the gear-train, which turns a shaft to which the butterfly valve is attached. Two microswitches signal the fully open/fully closed position of the isolation valves 33HN and 34HN to the cargo ventilation controller 10HN.
Accidental blockage of either isolation valve will cause a torque limit mechanism to disengage the gear-train. This protects the gear-train and butterfly valve from damage. A manual override and visual position indicator is connected to the end of the shaft at the top of the actuator.
The FWD cargo compartment isolation valves 4HN and 5HN are electrically operated butterfly valves. Each valve has a body assembly and an actuator housing which are bolted together and internally connected. The actuator housing contains a gear-train, two microswitches, a 28 VDC motor and an electrical connector. The 28 VDC motor drives the gear-train, which turns the butterfly valve through a shaft. Two microswitches senses the fully open/fully closed position of the isolation valve and give a signal to the cargo ventilation controller 10HN.
Accidental blockage of either isolation valve will cause a torque-limit mechanism to disengage the gear-train. This protects the gear-train and butterfly valve from damage. A manual override and visual position indicator is connected to the end of the shaft at the top of the actuator.
The AFT cargo compartment isolation valves 33HN and 34HN are electrically operated butterfly valves. Each consists of a body assembly and an actuator housing which are bolted together and internally connected. The actuator housing contains a gear-train, two microswitches, a 28 VDC motor and an electrical connector. The 28 VDC motor drives the gear-train, which turns a shaft to which the butterfly valve is attached. Two microswitches signal the fully open/fully closed position of the isolation valves 33HN and 34HN to the cargo ventilation controller 10HN.
Accidental blockage of either isolation valve will cause a torque limit mechanism to disengage the gear-train. This protects the gear-train and butterfly valve from damage. A manual override and visual position indicator is connected to the end of the shaft at the top of the actuator.
C. Extraction Fan
The FWD cargo extraction fan 6HN is installed in line with the extraction duct. It is powered by a three-phase four-pole induction motor that drives a fan-wheel. This fan runs on the ground and in flight when the differential pressure is below 1 psi. Thermo switches are installed inside the motor stators of the extraction fan. If the temperature of the stators gets to
140 DEG.C (284 DEG.F), the thermo switches isolate the electrical power to the fan.
The FWD cargo extraction fan 6HN is secured with clamps to brackets on the aircraft structure in the forward right-hand underfloor area. Arrows on the fan casing show the direction of airflow through the fan and the direction that the fan-wheel rotates. If the impeller breaks up, the casing is strong enough to contain the debris.
The AFT cargo extraction fan 35HN is installed in line with the extraction duct. It is powered by a three-phase four-pole induction motor that drives a fan-wheel. This fan runs continuously when the aircraft is on the ground or in flight. Thermo switches are installed inside the motor stators of the extraction fan. If the temperature of the stators gets to 140 DEG.C. (254 DEG.F), the thermo switches isolate the electrical supply to the fan.
The AFT cargo extraction fan 35HN is secured with clamps to brackets on the aircraft structure in the rear underfloor area. Arrows on the fan casing show the direction of airflow through the fan and the direction that the fan-wheel rotates. If the impeller breaks up, the casing is strong enough to contain the debris.
The FWD cargo extraction fan 6HN is installed in line with the extraction duct. It is powered by a three-phase four-pole induction motor that drives a fan-wheel. This fan runs on the ground and in flight when the differential pressure is below 1 psi. Thermo switches are installed inside the motor stators of the extraction fan. If the temperature of the stators gets to
140 DEG.C (284 DEG.F), the thermo switches isolate the electrical power to the fan.
The FWD cargo extraction fan 6HN is secured with clamps to brackets on the aircraft structure in the forward right-hand underfloor area. Arrows on the fan casing show the direction of airflow through the fan and the direction that the fan-wheel rotates. If the impeller breaks up, the casing is strong enough to contain the debris.
The AFT cargo extraction fan 35HN is installed in line with the extraction duct. It is powered by a three-phase four-pole induction motor that drives a fan-wheel. This fan runs continuously when the aircraft is on the ground or in flight. Thermo switches are installed inside the motor stators of the extraction fan. If the temperature of the stators gets to 140 DEG.C. (254 DEG.F), the thermo switches isolate the electrical supply to the fan.
The AFT cargo extraction fan 35HN is secured with clamps to brackets on the aircraft structure in the rear underfloor area. Arrows on the fan casing show the direction of airflow through the fan and the direction that the fan-wheel rotates. If the impeller breaks up, the casing is strong enough to contain the debris.
D. Pressure Switch
The pressure switch 21HN consists of a body with two pressure ports, a diaphragm, a spring, a microswitch and an electrical connector. One pressure port contains a filter and senses outside ambient pressure, the other senses cabin pressure. The diaphragm, when pressurized, exerts a force on a snap-action spring. When the differential pressure gets to 1 psi the spring will snap over and depress the microswitch actuator. This sends a signal to the cargo ventilation controller 10HN which stops the extraction fan 6HN. When pressure decreases, the microswitch returns to its original position, this removes the pressure signal and the extraction fan starts.
The pressure switch 21HN consists of a body with two pressure ports, a diaphragm, a spring, a microswitch and an electrical connector. One pressure port contains a filter and senses outside ambient pressure, the other senses cabin pressure. The diaphragm, when pressurized, exerts a force on a snap-action spring. When the differential pressure gets to 1 psi the spring will snap over and depress the microswitch actuator. This sends a signal to the cargo ventilation controller 10HN which stops the extraction fan 6HN. When pressure decreases, the microswitch returns to its original position, this removes the pressure signal and the extraction fan starts.
6. Operation/Control and Indicating
AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL
FWD Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL FWD Cargo-Compartment Ventilation - Schematic ** ON A/C NOT FOR ALL A. Operation
The extraction fan of the ventilation system for the AFT cargo compartment operates when the aircraft is on ground and in flight.
The cargo ventilation controller 10HN opens the isolation valves 33HN and 34HN. After the ventilation controller receives fully open signals from both valves, it starts the extraction fan 35HN.
The controller will close the isolation valves, and stop the extraction fan when:
The cargo ventilation controller 10HN opens the isolation valves 33HN and 34HN. After the ventilation controller receives fully open signals from both valves, it starts the extraction fan 35HN.
The controller will close the isolation valves, and stop the extraction fan when:
The cargo ventilation controller 10HN opens the isolation valves 4HN and 5HN. It receives a fully open signal from both valves and starts the extraction fan 6HN.
The controller stops the fan when the pressure switch 21HN indicates a differential pressure above 1 psi. The cargo compartment is then ventilated through differential pressure. When the differential pressure decreases below 1 psi, the pressure switch removes the pressure signal from the controller.
When the pressure signal is removed or the main landing gear is compressed, the controller starts the fan.
The controller will close the isolation valves and stop the extraction fan when:
The cargo ventilation controller 10HN opens the isolation valves 33HN and 34HN. After the ventilation controller receives fully open signals from both valves, it starts the extraction fan 35HN.
The controller will close the isolation valves, and stop the extraction fan when:
The extraction fan of the ventilation system for the AFT cargo compartment operates when the aircraft is on ground and in flight.
The cargo ventilation controller 10HN opens the isolation valves 33HN and 34HN. After the ventilation controller receives fully open signals from both valves, it starts the extraction fan 35HN.
The controller will close the isolation valves, and stop the extraction fan when:
- the isolation valve switch 36HN is selected OFF,
- the smoke detection control unit 10WQ detects smoke in the AFT cargo compartment (Ref. AMM D/O 26-16-00-00).
NOTE: In this case the isolation valves are closed/latched. Reopening is only possible in the absence of a smoke signal by power interrupt.
- the cargo SMOKE TEST switch 13WH located in the overhead panel (22VU) is pressed.
NOTE: If the smoke test switch is pressed, the controller will receive the test signal and the simulated smoke signal, the latter a few seconds later. In this case the isolation valves are closed but not latched. Reopening happens, if the SMOKE-signal is removed a few seconds earlier than the Test-signal, which is controlled by the smoke detection and control unit automatically.
The extraction fan of the ventilation system for the AFT cargo compartment operates on ground and in flight. The cargo ventilation controller 10HN opens the isolation valves 33HN and 34HN. After the ventilation controller receives fully open signals from both valves, it starts the extraction fan 35HN.
The controller will close the isolation valves, and stop the extraction fan when:
- the isolation valve switch 36HN is selected OFF,
- the smoke detection control unit 10WQ detects smoke in the AFT cargo compartment (Ref. AMM D/O 26-16-00-00),
NOTE: In this case the isolation valves are closed/latched. Reopening is only possible in the absence of a smoke signal by power interrupt.
- the cargo SMOKE TEST switch 13WH located in the overhead panel (22VU) is pressed.
NOTE: If the smoke test switch is pressed, the controller will receive the test signal and the simulated smoke signal, the latter a few seconds later. In this case the isolation valves are closed but not latched. Reopening happens, if the SMOKE-signal is removed a few seconds earlier than the Test-signal, which is controlled by the smoke detection and control unit automatically.
The ventilation system for the FWD cargo compartment operates in two different modes. The first mode operates when the aircraft is on ground and in flight up to a differential pressure of 1 psi. The second mode operates when the aircraft is in flight and the differential pressure is above 1 psi. The cargo ventilation controller 10HN opens the isolation valves 4HN and 5HN. It receives a fully open signal from both valves and starts the extraction fan 6HN.
The controller stops the fan when the pressure switch 21HN indicates a differential pressure above 1 psi. The cargo compartment is then ventilated through differential pressure. When the differential pressure decreases below 1 psi, the pressure switch removes the pressure signal from the controller.
When the pressure signal is removed or the main landing gear is compressed, the controller starts the fan.
The controller will close the isolation valves and stop the extraction fan when:
- the ditch switch 13HL is selected ON,
- the isolation valve switch 7HN is selected OFF,
- the CIDS director 1 (101RH) or the CIDS director 2 (102RH) detects smoke in the FWD cargo compartment (Ref. AMM D/O 26-16-00-00).
NOTE: In this case the isolation valves are closed/latched. Reopening is only possible in the absence of a smoke signal by power interrupt.
- the cargo SMOKE TEST switch 16WH located in the overhead panel (22VU) is pressed.
NOTE: If the smoke test switch is pressed, the controller will receive the test signal and the simulated smoke signal, the latter a few seconds later. In this case the isolation valves are closed but not latched. Reopening happens, if the SMOKE-signal is removed a few seconds earlier than the Test-signal, which is controlled by the CIDS 1 or the CIDS 2 automatically.
The extraction fan of the ventilation system for the AFT cargo compartment operates when the aircraft is on ground and in flight. The cargo ventilation controller 10HN opens the isolation valves 33HN and 34HN. After the ventilation controller receives fully open signals from both valves, it starts the extraction fan 35HN.
The controller will close the isolation valves, and stop the extraction fan when:
- the isolation valve switch 36HN is selected OFF,
- the smoke detection control unit 10WQ detects smoke in the AFT cargo compartment (Ref. AMM D/O 26-16-00-00).
NOTE: In this case the isolation valves are closed/latched. Reopening is only possible in the absence of a smoke signal by power interrupt.
- the cargo SMOKE TEST switch 16WH located in the overhead panel (22VU) is pressed.
NOTE: If the smoke test switch is pressed, the controller will receive the test signal and the simulated smoke signal, the latter a few seconds later. In this case the isolation valves are closed but not latched. Reopening happens, if the SMOKE-signal is removed a few seconds earlier than the Test-signal, which is controlled by the smoke detection and control unit automatically.
B. Control and Indication
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL
The AFT ISOL VALVE switch 36HN is installed on panel 22VU in the cockpit overhead panel. It controls the isolation valves 33HN, 34HN and the extraction fan 35HN. The cargo ventilation controller 10HN will only start the fan if a fully open signal is received from both isolation valves. With the isolation valve switch 36HN pressed-in, the isolation valves 33HN and 34HN open fully and the extraction fan 35HN starts. With the isolation valve switch pressed-out, OFF light comes on white, the isolation valves close and the extraction fan stops. The FAULT light comes on amber if either isolation valve is not fully open or fully closed.
If there is an isolation valve disagree (not fully open or not fully closed) the ventilation controller will also send a signal to the Flight Warning Computer (FWC).
If there is an extraction fan fault, the ventilation controller gives a signal to the FWC via the zone controller 8HK which generates the appropriate failure message for the Centralized Fault-Display System (CFDS) (Ref. 21-63-00 or 31-32-00).
The AFT ISOL VALVE switch 36HN is installed on panel 22VU in the cockpit overhead panel. It controls the isolation valves 33HN, 34HN and the extraction fan 35HN. The cargo ventilation controller 10HN will only start the fan if a fully open signal is received from both isolation valves. With the isolation valve switch 36HN pressed-in, the isolation valves 33HN and 34HN open fully and the extraction fan 35HN starts. With the isolation valve switch pressed-out, OFF light comes on white, the isolation valves close and the extraction fan stops. The FAULT light comes on amber if either isolation valve is not fully open or fully closed.
If there is an isolation valve disagree (not fully open or not fully closed) the ventilation controller will also send a signal to the Flight Warning Computer (FWC).
If there is an extraction fan fault, the ventilation controller gives a signal to the FWC via the ACSC1 47HH which generates the appropriate failure message for the Centralized Fault-Display System (CFDS) (Ref. 21-63-00 or 31-32-00).
The FWD ISOL VALVE switch 7HN installed on panel 22VU in the cockpit overhead panel, controls the isolation valves 4HN, 5HN and the extraction fan 6HN. The cargo ventilation controller 10HN will only start the fan if a fully open signal is received from both isolation valves.
With the isolation valve switch 7HN pressed-in, the isolation valves 4HN and 5HN open fully and the extraction fan 6HN starts. With the isolation valve switch pressed-out, OFF light comes on white, the isolation valves close and the extraction fan stops. The FAULT light comes on amber if either isolation valve is not fully open or fully closed.
If there is an isolation valve disagree (not fully open or not fully closed) the ventilation controller will send a signal to the Flight Warning Computer (FWC).
If there is an extraction fan fault, the ventilation controller gives a signal to the FWC via the air conditioning system controller (ACSC1) 47HH which generates the appropriate failure message for the Centralized Fault-Display System (CFDS) (Ref. 21-63-00 or 31-32-00).
AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL AFT Cargo-Compartment Ventilation-System - Component Location ** ON A/C NOT FOR ALL If there is an isolation valve disagree (not fully open or not fully closed) the ventilation controller will also send a signal to the Flight Warning Computer (FWC).
If there is an extraction fan fault, the ventilation controller gives a signal to the FWC via the zone controller 8HK which generates the appropriate failure message for the Centralized Fault-Display System (CFDS) (Ref. 21-63-00 or 31-32-00).
The AFT ISOL VALVE switch 36HN is installed on panel 22VU in the cockpit overhead panel. It controls the isolation valves 33HN, 34HN and the extraction fan 35HN. The cargo ventilation controller 10HN will only start the fan if a fully open signal is received from both isolation valves. With the isolation valve switch 36HN pressed-in, the isolation valves 33HN and 34HN open fully and the extraction fan 35HN starts. With the isolation valve switch pressed-out, OFF light comes on white, the isolation valves close and the extraction fan stops. The FAULT light comes on amber if either isolation valve is not fully open or fully closed.
If there is an isolation valve disagree (not fully open or not fully closed) the ventilation controller will also send a signal to the Flight Warning Computer (FWC).
If there is an extraction fan fault, the ventilation controller gives a signal to the FWC via the ACSC1 47HH which generates the appropriate failure message for the Centralized Fault-Display System (CFDS) (Ref. 21-63-00 or 31-32-00).
The FWD ISOL VALVE switch 7HN installed on panel 22VU in the cockpit overhead panel, controls the isolation valves 4HN, 5HN and the extraction fan 6HN. The cargo ventilation controller 10HN will only start the fan if a fully open signal is received from both isolation valves.
With the isolation valve switch 7HN pressed-in, the isolation valves 4HN and 5HN open fully and the extraction fan 6HN starts. With the isolation valve switch pressed-out, OFF light comes on white, the isolation valves close and the extraction fan stops. The FAULT light comes on amber if either isolation valve is not fully open or fully closed.
If there is an isolation valve disagree (not fully open or not fully closed) the ventilation controller will send a signal to the Flight Warning Computer (FWC).
If there is an extraction fan fault, the ventilation controller gives a signal to the FWC via the air conditioning system controller (ACSC1) 47HH which generates the appropriate failure message for the Centralized Fault-Display System (CFDS) (Ref. 21-63-00 or 31-32-00).