Removal of the Pressure Service Check-Valve

TASK 36-11-56-000-001-A
Removal of the Pressure Service Check-Valve

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

FIN: 7270HM
FIN: 7272HM

1. Reason for the Job
Self explanatory
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	2	CAP - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
191BB, 192FB

C. Referenced Information

REFERENCE	DESIGNATION
Pressure Service Check-Valve 7270HM, 7272HM

3. Job Set-up
Subtask 36-11-56-865-050-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AIR BLEED/ENG 1/CTL	3HA1	D12
49VU	AIR BLEED/ENG 1/MONG	2HA1	D11
** ON A/C ALL
49VU	AIR BLEED/X FEED/VALVE/BAT	2HV	D13
** ON A/C NOT FOR ALL
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
** ON A/C NOT FOR ALL
122VU	AIR BLEED/ENG 2/CTL	3HA2	Z23
122VU	AIR BLEED/ENG 2/MONG	2HA2	Z22
** ON A/C ALL
122VU	AIR BLEED/X FEED VALVE/NORM	1HV	Z20
** ON A/C NOT FOR ALL
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22

Subtask 36-11-56-860-050-A

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

in the cockpit on the Engine Control Panel 115VU to tell persons not to start the engine(s)
in the cockpit on the 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.

(2) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below zone 190.

Subtask 36-11-56-010-050-A

C. Remove the access panel 191BB or 192FB.

4. Procedure
Subtask 36-11-56-020-050-A

A. Removal of the Pressure Service Check-Valve
(1) Loosen the union (1) of the elbow (5).
(2) Remove the elbow (5) from the pressure service check-valve (2).
(3) Remove the pressure service check-valve (2) and the O-ring (3) from the connector (4).
(4) Discard the O-ring (3).
(5) Put the CAP - BLANKING on the union (1) of the elbow (5) and the connector (4).

[Rev.10 from 2021] 2026.04.01 12:38:06 UTC