Reactivation of the APU Bleed Check-Valve

TASK 36-12-00-440-803-A
Reactivation of the APU Bleed Check-Valve

WARNING: MAKE SURE THAT THE PNEUMATIC SYSTEM IS DEPRESSURIZED BEFORE YOU START WORK. PRESSURIZED AIR CAN CAUSE INJURY TO PERSONNEL.

FIN: 7260HM

1. Reason for the Job
MMEL 36-22-03A
APU LEAK DETECTION LOOP
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.5 and 0.4 m.daN (44.25 and 35.40 lbf.in )

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
151CW, 151SW, 197BB, 197KB

C. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
10	BLANKING CAP	AIPC 36-12-83-03-600

D. Referenced Information

REFERENCE	DESIGNATION
TASK 12-33-21-618-001-A-02	Pre-conditioning with the APU
TASK 36-22-17-000-001-A	Removal of the APU Overheat Sensing-Elements
TASK 36-22-17-400-001-A	Installation of the APU Overheat Sensing-Elements
TASK 52-30-00-860-001-A	Open the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
TASK 52-30-00-860-002-A	Close the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
AIPC 36-12-83-03
APU Bleed Check-Valve - Blanking Cap

3. Job Set-up
Subtask 36-12-00-860-089-A

A. Aircraft Maintenance Configuration
(1) Put the WARNING NOTICE(S) in position:

In the cockpit, on engine control panel 115VU, to tell persons not to start the engine(s)
In the cockpit, on AIR COND overhead control panel 30VU, to tell persons not to push in the APU BLEED pushbutton switch
On the HP ground connector, to tell persons not to pressurize the pneumatic system.

Subtask 36-12-00-010-062-A

B. Get Access
(1) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position.
(2) Remove access panel:
(a) If installed, remove access panel 197BB
(b) If installed, remove access panel 197KB.
(3) Open the aft cargo-compartment door (Ref. AMM TASK 52-30-00-860-001).
(4) In the aft cargo compartment, remove the sidewall panel:
(a) If installed, remove sidewall panel 151CW, or
(b) If installed, remove sidewall panel 151SW.

Subtask 36-12-00-865-074-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AIR BLEED/X FEED/VALVE/BAT	2HV	D13
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22
122VU	AIR BLEED/X FEED VALVE/NORM	1HV	Z20

4. Procedure
Subtask 36-12-00-020-053-A

A. Reactivation of the APU Bleed Check-Valve

NOTE: Refer to AIPC 36-12-83-03 for the AIPC 36-12-83-03-600 BLANKING CAP (10) of the APU bleed check-valve (6) to do the procedure.

(1) Disengage the overheat sensing elements that are near the APU bleed check-valve (6) from the ducts (9) and (4) (Ref. AMM TASK 36-22-17-000-001).
(2) Loosen the nut of the clamp (3) and remove the clamp (3).
(3) Loosen the nut of the clamp (8) and remove the clamp (8).
(4) Remove the nuts (2) and the washers (1).
(5) Hold the blanking cap (10) and remove the bolts (7).
(6) Remove the blanking cap (10) and the seal (5).
(7) Put the APU bleed check-valve (6) with the seal (5) in position.
(8) Install the bolts (7), washers (1) and nuts (2).
(9) Tighten the nuts (2).
(10) Install the clamps (3) and (8).
(11) TORQUE the nuts of the clamps (3) and (8) to between 0.5 and 0.4 m.daN (44.25 and 35.40 lbf.in )

.
(12) Attach the overheat sensing elements that are near the APU bleed check-valve (6) to the ducts (9) and (4) (Ref. AMM TASK 36-22-17-400-001).

Subtask 36-12-00-865-075-A

B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AIR BLEED/X FEED/VALVE/BAT	2HV	D13
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22
122VU	AIR BLEED/X FEED VALVE/NORM	1HV	Z20

Subtask 36-12-00-710-061-A

C. Leak Test of the Pneumatic Connections
(1) Do the ground air pre-conditioning with the APU (Ref. AMM TASK 12-33-21-618-001).
(2) Make sure that there are no leaks between the connections of the APU bleed check-valve (6) and the ducts (4) and (9).

5. Close-up
Subtask 36-12-00-410-062-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install access panel:
(a) If removed, install access panel 197BB
(b) If removed, install access panel 197KB.
(3) In the aft cargo compartment, install the sidewall panel:
(a) If removed, install sidewall panel 151CW, or
(b) If removed, install sidewall panel 151SW.
(4) Close the aft cargo-compartment door (Ref. AMM TASK 52-30-00-860-002).

Subtask 36-12-00-942-059-A

B. Aircraft Maintenance Configuration
(1) Put the aircraft back to the serviceable condition.
(2) Remove the WARNING NOTICE(S).
(3) Remove the access platform(s).

[Rev.10 from 2021] 2026.04.01 12:39:17 UTC