APU Compressor Cleaning (APS3200)

TASK 49-20-00-100-807-A
APU Compressor Cleaning (APS3200)

WARNING: WAIT A MINIMUM OF 1 HOUR AFTER THE APU SHUTDOWN TO LET THE INTERNAL TEMPERATURE DECREASE TO BETWEEN 55 AND 60 DEG. THERE IS A RISK OF BURNS IF YOU APPLY CLEANING FLUID WHEN THE APU IS TOO HOT.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

1. Reason for the Job
High EGT as a result of compressor contamination.

NOTE: This procedure will not correct all APU problems. You must do the correct trouble-shooting procedures before the compressor is cleaned.
Complete these tasks after contamination of the engine with:

fuel,
corrosive materials.

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE
No specific	AR	CAP - BLANKING
No specific	AR	CONTAINER 1 L (1/4 USGAL)
No specific	AR	PLUG - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WATER - DEIONIZED
No specific	AR	WATER - DISTILLED
No specific	Torque wrench: range to between 0.495 and 0.405 m.daN (43.81 and 35.84 lbf.in )
No specific	Torque wrench: range to between 1.13 and 1.02 m.daN (100.00 and 90.27 lbf.in )
98A28007570000	1	ADAPTER - VENT AND DRAIN VALVE, APU
98A49007625001	1	DEVICE - CLEANING, APU

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.03ABA1)	Synthetic base Lubricating Oil-Turbine Engine - -
(Material No.03ABB1)	Synthetic base Lubricating Oil-Turbine Engine Low Temp. -
(Material No.03FAB1)	Mineral Oil base Grease-- Vaseline or Petrolatum -
(Material No.08AJA1)	Aqueous Cleaner-Turbine Engine Gas Path - -
(Material No.08AJA9)	Aqueous Cleaner-Turbine Engine Gas Path - Legacy
(Material No.08BBD1)	Non Aqueous Cleaner-- Isopropyl Alcohol -
(Material No.14QFC1)	Wire-Locking Dia: 0.8 mm CRES -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315AL, 316AR

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
20	O-RING	AIPC 49-21-04-53-030
22	O-RING	AIPC 49-21-04-54-030
20	O-RING	AIPC 49-21-84-20-470
22	O-RING	AIPC 49-21-84-20-470

E. Referenced Information

REFERENCE	DESIGNATION
TASK 23-44-00-700-001-A	Operational Test of the Service Interphone
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
TASK 49-00-00-710-008-A	Operational Test of the APU
TASK 52-41-00-010-001-A	Open the APU Doors for Access
TASK 52-41-00-410-001-A	Close the APU Doors after Access
Cleaning Device - Installation
APU - Fuel Vent and Drain Valve, Ignition Unit
APU - Tube Assembly

3. Job Set-up
Subtask 49-20-00-860-116-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration.
(1) Make sure that the hydraulic systems are depressurized (Ref. AMM TASK 29-14-00-614-001).
(2) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).
(3) Make sure that the electronic racks are correctly ventilated.
(4) Connect the service interphone to the aircraft (Ref. AMM TASK 23-44-00-700-001).

Subtask 49-20-00-865-115-A ** ON A/C NOT FOR ALL

B. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	APU/FUEL/BLOW OFF/PUMP	2QC	B14
121VU	APU/FUEL/BLOW OFF/CTL	1QC	K39
121VU	APU/FUEL/LP VALVE/CTL	1QF	M40
121VU	APU/FUEL/LP VALVE/SPLY	2QF	M39
121VU	APU/FUEL/PUMP/CTL	3QC	M38

Subtask 49-20-00-010-083-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE below the APU access doors 316AR and 315AL.
(2) Open the APU access doors 315AL 316AR (Ref. AMM TASK 52-41-00-010-001).
(3) Set the LIGHT control switch 11LJ to the ON position.

4. Procedure
Subtask 49-20-00-860-117-A ** ON A/C NOT FOR ALL

A. APU System Maintenance Configuration
(1) Disconnect the electrical connector P19 from the Fuel Control Unit.
(2) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(3) Drain and disconnect the Fuel Inlet Line

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

CAUTION: PUT PLASTIC CAPS OR PLUGS ON ALL FUEL AND/OR LUBRICATION SYSTEM COMPONENTS AND LINES. IF YOU USE TAPE, CLOTH, OR METAL CAPS ON THEM, YOU CAN DAMAGE THE APU.

CAUTION: YOU MUST USE TWO WRENCHES AND HOLD THE COMPONENT WHEN YOU REMOVE/INSTALL THE PIPE COUPLINGS AND/OR UNIONS. THIS PREVENTS DAMAGE TO THE COMPONENT.

(a) Put the CONTAINER 1 L (1/4 USGAL) in position below the fuel control unit and the vent and drain valve (12).
(b) Remove the blanking cap (13) from the LP fuel inlet vent and drain valve (12).
(c) Install the 98A28007570000 ADAPTER - VENT AND DRAIN VALVE, APU to the vent and drain valve (12).
(d) Drain the unwanted fuel into the container.
(e) Remove the 98A28007570000 ADAPTER - VENT AND DRAIN VALVE, APU from the vent and drain valve.
(f) Install the blanking cap (13).
(g) Remove and discard the lockwire and disconnect the fuel inlet line (14) from the vent and drain valve (12).
(h) Put the PLUG-BLANKING in each disconnected line end.
(i) Put the main fuel inlet-pipe in the stowage bracket attached to the firewall of the APU compartment.
(j) Remove the container below the vent and drain valve (12).
(4) Move the IGV Actuator Rod at the IGV position indicator from the closed end to the open end, to provide maximum access to load compressor for the cleaning mixture.
(5) Disconnect the Power Compressor Discharge (PCD) lines as follows:
(a) Remove the tube assembly (Pneu - Sensor PCD) (17) (Ref. AIPC 49-21-04-53-120).
(b) Disconnect the tube assembly (Pneu - Duct to Sensor PCD) (23) (Ref. AIPC 49-21-04-54-170) from the Bleed Control Valve (BCV) port.
(c) Put the PLUG-BLANKING in each disconnected line end.
(d) Disconnect the tube assembly (Pneu - PCD to Gearbox) (18) (Ref. AIPC 49-21-04-53-010), from the combustor side.
(e) Put the PLUG-BLANKING in each disconnected line end.
(6) Disconnect the electrical connector P10 (16) from the Ignition Unit (15).
(7) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(8) Install the 98A49007625001 DEVICE - CLEANING, APU:
(a) Install the mounting plate (1) on the APU rear lower mount boss with the knurled screw (2).
(b) Attach the tube support assembly (10) to the mount plate (1) with the knurled screws (3).
(c) Clamp the sprayer unit (11) to the support assembly (10) with the clamp plate (9), the screws (4), the washers (5) and (6) and the nuts (7).
(d) Position the sprayer unit nozzles in the APU air intake as required.
(9) Prepare the cleaning mixture:
(a) In the cleaning device container, prepare a mixture as follows:
Use Non Aqueous Cleaner-- Isopropyl Alcohol - (Material No.08BBD1) with Aqueous Cleaner-Turbine Engine Gas Path - Legacy (Material No.08AJA9) or Aqueous Cleaner-Turbine Engine Gas Path - - (Material No.08AJA1)

AMBIENT TEMPERATURE	CLEANING PRODUCT	WATER	ISOPROPYL ALCOHOL
over +5 deg C. (+41 deg F).	20%	80%	0%
-8 to +5 deg C. (+18 to +41 deg F).	16%	66%	18%
-24 to -8 deg C. (-11 to +18 deg F).	13%	54%	33%

(b) Close the container and pressurize with compressed air as needed.

Subtask 49-20-00-160-052-A ** ON A/C NOT FOR ALL

CAUTION: MAKE SURE THAT YOU HAVE THE CORRECT FIRE FIGHTING EQUIPMENT AVAILABLE. THE APU FIRE EXTINGUISHING SYSTEM IS NOT SUFFICIENT TO EXTINGUISH A FIRE IF THE ACCESS DOORS 315AL AND 316AR ARE OPEN/ REMOVED. KEEP OPERATION OF THE APU TO A MINIMUM WHEN THE ACCESS DOORS ARE OPEN/REMOVED.

B. Compressor wash

NOTE: APU run with open doors

make sure that the access platform can not move.
make sure that the fire fighting equipment and the necessary persons to monitor the start and operation of the APU are available.
make sure that no persons or loose equipment are in the danger areas.

(1) On the C/B panel 121VU, make sure that these C/Bs are closed:
1KD.. APU/ECB/SPLY .... 41L;
2KD.. APU/APU/CTL ..... 42L.
(2) On the overhead panel 25VU:

push the APU MASTER SW p/bsw,
push the APU START SW p/bsw to on.

(3) When the APU starts to crank apply the cleaning fluid solution into the APU air inlet with a flow rate of 3.0 l (0.7925 USgal)/per min to 3.5 l (0.9246 USgal)/per min.

NOTE: The recommended spray nozzle pressure is 2.8 bar (40.6106 psi) to 4.1 bar (59.4655 psi) at the recommended flow rate.

NOTE: The APU will crank to approx 15% speed and then decelerate to 0% speed.

(4) Stop to apply the cleaning fluid solution at 0% speed.
(5) Wait 15 minutes to allow cleaning fluid solution to soak.
(6) Do steps 1 thru 4 again.
(7) Flush the engine with WATER - DEIONIZED, if not available use WATER - DISTILLED.
(8) Wait 5 minutes and flush engine again with deionized water, if not available use clean clear water.

Subtask 49-20-00-860-118-A ** ON A/C NOT FOR ALL

C. Put the system back to the serviceable condition.
(1) Remove the cleaning device:
(a) Disconnect and remove the sprayer (11) from the support assembly (10).
(b) Remove the knurled screws (3) and remove the cleaning device.
(c) Remove the knurled screw (2) and the mount plate (1) from the APU rear lower mount boss.
(2) Remove any blanking plugs from the disconnect line ends.
(3) Connect the electrical connector P10 (16) to the ignition exciter (15).
(4) Apply a thin layer of Mineral Oil base Grease-- Vaseline or Petrolatum - (Material No.03FAB1) on the new AIPC 49-21-04-53-030 O-RING (20) or AIPC 49-21-84-20-470 O-RING (20).
(5) Install the new o-ring (20) at the tube assembly (18).
(6) Apply a thin layer of Synthetic base Lubricating Oil-Turbine Engine - - (Material No.03ABA1) or Synthetic base Lubricating Oil-Turbine Engine Low Temp. - (Material No.03ABB1) on the screws (19).
(7) Install the tube assembly (18) at the combustors side.
(8) TORQUE the screws (19) with to between 0.495 and 0.405 m.daN (43.81 and 35.84 lbf.in )

.
(9) Apply a thin layer of Mineral Oil base Grease-- Vaseline or Petrolatum - (Material No.03FAB1) on the new AIPC 49-21-04-54-030 O-RING (22) or AIPC 49-21-84-20-470 O-RING (22).
(10) Install the new o-ring (22) at the tube assembly (23).
(11) Apply a thin layer of Synthetic base Lubricating Oil-Turbine Engine - - (Material No.03ABA1) or Synthetic base Lubricating Oil-Turbine Engine Low Temp. - (Material No.03ABB1) on the screws (21).
(12) Install the tube assembly (23) at BCV port.
(13) TORQUE the screws (21) to between 0.495 and 0.405 m.daN (43.81 and 35.84 lbf.in )

.
(14) Install the tube assembly (17), and TORQUE to between 1.13 and 1.02 m.daN (100.00 and 90.27 lbf.in )

.
(15) Safety the fuel inlet line (14):

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

(a) Reconnect the fuel inlet line (14), and safety it with 14QFC1Wire-Locking Dia: 0.8 mm CRES -.
(16) Push the IGV Actuator Rod to close the IGV's.
(17) Reconnect the electrical connector P19 to the fuel control unit.

Subtask 49-20-00-710-070-A ** ON A/C NOT FOR ALL

D. Operational Test
(1) Do the operational test of the APU (Ref. AMM TASK 49-00-00-710-008), and run the APU for 5 minutes to make sure the APU is dry.

NOTE: During the wash procedure the following FAULT MESSAGES will be stored in ECB BITE Memory:

FUEL CTL UNIT P19
IGNITION UNIT P10
NO FLAME APU AUTO SHUTDOWN

5. Close-up
Subtask 49-20-00-410-084-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Disconnect and remove the service interphone.

NOTE: During the wash procedure the following FAULT MESSAGES will be stored in ECB BITE Memory:

FUEL CTL UNIT P19
IGNITION UNIT P10
NO FLAME APU AUTO SHUTDOWN

(3) Set the LIGHT control switch 11LJ to the OFF position.
(4) Close the APU access doors 315AL, 316AR (Ref. AMM TASK 52-41-00-410-001).
(5) Remove the access platform(s).

Subtask 49-20-00-860-119-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Put the related hydraulic system in the pressurized configuration (Ref. AMM TASK 29-00-00-864-001).
(2) De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).

[Rev.10 from 2021] 2026.04.01 01:28:43 UTC