W DOC AIRBUS | AMM A320F

APU Load Compressor Cleaning because of fluid ingestion (131-9(A))


TASK 49-20-00-100-004-A
APU Load Compressor Cleaning because of fluid ingestion (131-9(A))


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
APU Load Compressor cleaning as a result of fluid ingestion from Aircraft/APU leaks that goes into the APU inlet.
NOTE: This procedure will not correct all APU problems. All fluid leaks must be corrected before the cleaning procedure.
Complete this task after contamination of the engine with:
  • fuel,
  • corrosive materials,
  • oils.
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
CLEANING EQUIPMENT - COMPRESSOR
No specific
AR
PLUG - BLANKING
No specific
AR
PUMP - HAND
No specific
AR
SAFETY CLIP - CIRCUIT BREAKER
No specific
Torque wrench: range to between 0.616 and 0.504 m.daN (54.51 and 44.60 lbf.in ) T
98A49007625001
1
DEVICE - CLEANING, APU
98L12003001000
AR
HARNESS,SAFETY
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.08ABC1)
Aqueous Cleaner-Aircraft Exterior Pressure Spraying -
(Material No.08AJA9)
Aqueous Cleaner-Turbine Engine Gas Path - Legacy
(Material No.14SBA1)
Textile-Lint free Cotton -
 C. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
315AL, 316AR
 D. Referenced Information
REFERENCE
DESIGNATION
TASK 21-00-00-615-803-A
Level B Decontamination of the Environmental Control System (ECS)
TASK 21-00-00-615-804-A
Level C Decontamination of the Environmental Control System (ECS)
TASK 23-44-00-860-001-A
Operation of the Service Interphone System
TASK 24-42-00-861-001-A
Energize the Ground Service Network from the External Power
TASK 24-42-00-862-001-A
De-energize the Ground Service Network Supplied from the External Power
TASK 29-00-00-864-001-A
Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-00-00-860-008-A
APU Start by External Power
TASK 49-00-00-860-008-A-01
APU Start by Batteries
TASK 49-00-00-860-009-A
APU Shutdown by External Power (131-9(A))
TASK 49-00-00-860-009-A-01
APU Shutdown by Batteries (131-9(A))
TASK 49-16-00-210-802-A
General Visual Inspection of APU Air Inlet Plenum and APU Air Intake (131-9(A))
TASK 49-51-51-000-004-A
Removal of the Load Control Valve (131-9(A))
TASK 49-51-51-400-004-A
Installation of the Load Control Valve (131-9(A))
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
3. Job Set-up
Subtask 49-20-00-860-071-A ** ON A/C NOT FOR ALL
A. Aircraft Maintenance Configuration
   (1) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).
   (2) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-00-00-864-001).
   (3) Connect the service interphone to the aircraft (Ref. AMM TASK 23-44-00-860-001).
Subtask 49-20-00-865-081-A ** ON A/C NOT FOR ALL
B. Open, safety and tag this(these) circuit breaker(s):
PANELDESIGNATIONFINLOCATION
** ON A/C NOT FOR ALL
121VUAPU/APU/CTL2KDL42
121VUAPU/ECB/SPLY1KDL41
Subtask 49-20-00-010-065-A ** ON A/C NOT FOR ALL
C. Get Access
WARNING: BEFORE YOU START WORK, YOU MUST PUT ON A SAFETY HARNESS AND ATTACH IT TO THE ACCESS PLATFORM. WITHOUT A SAFETY HARNESS, YOU CAN FALL. THIS CAN KILL YOU OR CAUSE YOU INJURY.
   (1) Put on and attach the HARNESS, SAFETY before you start work in the work area.
   (2) Put the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE below APU access doors 315AL and 316AR.
   (3) Open APU access doors 315AL and 316AR (Ref. AMM TASK 52-41-00-010-001).
   (4) Set the light switch 11LJ to the ON position.
4. Procedure
Subtask 49-20-00-020-059-A ** ON A/C NOT FOR ALL
A. Disconnect the Bleed Air Duct
F Bleed Air Duct - APU ** ON A/C NOT FOR ALL
   (1) Remove the clamp (2).
   (2) Install the PLUG - BLANKING on the bleed air duct (3).
NOTE: Do not cover the flange of the APU load control valve (1).
   (3) Disconnect the electrical connector P12 from the load control valve.
   (4) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
Subtask 49-20-00-100-058-A ** ON A/C NOT FOR ALL
B. Preparation and Cleaning
F Cleaning Device ** ON A/C NOT FOR ALL
   (1) Install the 98A49007625001 DEVICE - CLEANING, APU and the mount assembly on the APU.
     (a) Install the mounting plate (14) and the knurled screw (15) on the APU rear-lower mount-boss.
     (b) Attach the tube support assembly (16) to the mount plate (14).
     (c) Tighten the knurled screws (15) and (17).
     (d) Attach the sprayer unit (23) to the support assembly (16) with the clamp plate (22).
     (e) Install the screws (18), washers (19) and (21).
     (f) Tighten the nuts (20).
   (2) Turn and adjust the two spray nozzles (24) to spray only the APU load compressor.
     (a) Make sure that you do not clean the APU power compressor.
   (3) Make sure that the spray nozzle assembly is correctly installed and tightened.
WARNING: WHEN YOU USE COMPRESSED AIR:
  • USE THE CORRECT PROTECTION (FACE SHIELD OR GOGGLES)
  • DO NOT POINT THE AIRFLOW AT YOURSELF OR OTHER PERSONS.
LOOSE PARTICLES AND/OR HIGH PRESSURE AIR CAN CAUSE INJURY.
   (4) Prepare 18.0 l (4.7551 USgal) of the compressor cleaning-solution:
     (a) Mix 12.0 l (3.1700 USgal) of the de-mineralized water and 6.0 l (1.5850 USgal) of the Aqueous Cleaner-Turbine Engine Gas Path - Legacy (Material No.08AJA9) to make the cleaning solution.
     (b) Fill the container of the CLEANING EQUIPMENT - COMPRESSOR with 9.0 l (2.3775 USgal) of the cleaning solution.
     (c) Close the container and make sure that it is correctly sealed.
     (d) Use the PUMP - HAND on the compressor cleaning device and pressurize the container to 5 bar (72.5189 psi).
   (5)
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.
     (a) Before you operate the APU when the doors are open, do the steps that follow:
       1 Make sure that the access platform cannot move.
       2 Make sure that the fire fighting equipment and the persons necessary to monitor the start and the operation of the APU are available.
       3 Make sure that no persons or loose items of equipment are in the dangerous areas.
     (b) Start and operate the APU (Ref. AMM TASK 49-00-00-860-008).
   (6) Spray the cleaning solution only into the APU load compressor until the compressor cleaning device is empty.
     (a) Make sure that you do not clean the APU power compressor.
   (7) Use the PUMP - HAND to keep the pressure in the compressor cleaning device at approximately 5 bar (72.5189 psi).
   (8) Let the APU operate for two minutes with no cleaning fluid in the APU load compressor. This is to make sure that the bleed air components are dry.
   (9) Release the pressure from the compressor cleaning device.
   (10) Open the compressor-cleaning device container and fill it with 9.0 l (2.3775 USgal) of the cleaning solution.
   (11) Close the container and make sure that it is correctly sealed.
   (12) Operate the PUMP - HAND on the compressor cleaning device and pressurize the container to 5 bar (72.5189 psi).
   (13) Spray the cleaning solution only into the APU load compressor for a second time until the cleaning device is empty.
     (a) Make sure that you do not clean the APU power compressor.
   (14) Use the PUMP - HAND and keep the pressure in the compressor cleaning device at approximately 5 bar (72.5189 psi).
   (15) Let the APU operate for ten more minutes. This is to make sure that the bleed components are dry.
   (16) Stop the APU (Ref. AMM TASK 49-00-00-860-009).
   (17) Remove the 98A49007625001 DEVICE - CLEANING, APU:
     (a) Remove the knurled screws (17) and remove the cleaning device.
     (b) Remove the knurled screw (15) and the mount plate (14) from the rear-lower mount boss.
   (18) Make sure that there is no contamination (or remaining cleaning solution) at the load control-valve inlet or in the load compressor-discharge duct:
     (a) Remove the load control valve (Ref. AMM TASK 49-51-51-000-004).
     (b) Use a Textile-Lint free Cotton - (Material No.14SBA1) and the Aqueous Cleaner-Aircraft Exterior Pressure Spraying - (Material No.08ABC1) to manually remove the contamination from the load control valve.
     (c) Install the load control valve (Ref. AMM TASK 49-51-51-400-004).
Subtask 49-20-00-420-054-A ** ON A/C NOT FOR ALL
C. Connection of the Bleed air Duct
   (1) Remove the blanking plug from the bleed air duct (3).
   (2) Make sure that the bleed air duct (3) is clean and dry.
     (a) If necessary, clean the bleed air duct (3) (Ref. AMM TASK 21-00-00-615-803) or (Ref. AMM TASK 21-00-00-615-804).
   (3) Connect the bleed air duct (3) to the load control valve (1) with the clamp (2).
CAUTION: DO NOT TORQUE THE V-CLAMP(S) TO MORE THAN THE SPECIFIED VALUE. THIS CAN CAUSE DAMAGE TO THE FLANGE SURFACES.
   (4) TORQUE the clamp (2) to between 0.616 and 0.504 m.daN (54.51 and 44.60 lbf.in ) T.
   (5) Remove the blanking caps and connect the electrical connector P12 to the Load Control Valve.
Subtask 49-20-00-100-064-A ** ON A/C NOT FOR ALL 5. Close-up
Subtask 49-20-00-410-067-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) Set the light switch 11LJ to the OFF position.
   (3) Close APU access doors 315AL and 316AR (Ref. AMM TASK 52-41-00-410-001).
   (4) Remove the access platform(s).
   (5) Remove the 98L12003001000 HARNESS,SAFETY.
Subtask 49-20-00-865-082-A ** ON A/C NOT FOR ALL
B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
PANELDESIGNATIONFINLOCATION
** ON A/C NOT FOR ALL
121VUAPU/APU/CTL2KDL42
121VUAPU/ECB/SPLY1KDL41
Subtask 49-20-00-860-072-A ** ON A/C NOT FOR ALL
C. Aircraft Maintenance Configuration
   (1) Pressurize the aircraft hydraulic systems
(Ref. AMM TASK 29-00-00-864-001).
   (2) Remove the WARNING NOTICE(S).
   (3) De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).
[Rev.10 from 2021] 2026.04.01 01:28:47 UTC