Operational Check of ACT FWD (4.1) Overpressure Protector

TASK 28-28-00-710-802-A
Operational Check of ACT FWD (4.1) Overpressure Protector

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

1. Reason for the Job
Refer to the MPD TASK: 282800-21
OPERATIONAL CHECK OF ACT FWD (4.1) OVERPRESSURE PROTECTOR
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	AIR SOURCE 0,3 BAR (4,38 PSI)
No specific	1	WARNING NOTICE(S)

B. Referenced Information

REFERENCE	DESIGNATION
TASK 28-00-00-910-001-A	Fuel Safety Procedures

3. Job Set-up
Subtask 28-28-00-860-237-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Obey the fuel safety procedures (Ref. AMM TASK 28-00-00-910-001).
(2) Put a WARNING NOTICE(S) in position on:

Refuel/defuel panel 800VU,
Fuel panels 28VU and 40VU,
to tell persons not to operate the refuel/defuel system.

Subtask 28-28-00-010-122-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Remove ACT4.1 from the forward cargo compartment (Ref. AMM D/O 28-11-27-00).

4. Procedure
Subtask 28-28-00-710-078-A ** ON A/C NOT FOR ALL

A. Operational Check of ACT FWD (4.1) Overpressure Protector
(1) Install a blank cap with a test connector on the aft opening of the vent-line of ACT4.1.
(2) Connect a regulated AIR SOURCE 0,3 BAR (4,38 PSI) to the test connector.
(3) If necessary, remove the blank cap from the forward opening of the vent-line.
(4) Do this test:

ACTION	RESULT
1.On ACT4.1: Close the forward ACT vent isolation-valve.
2.On the air source: Carefully pressurize the vent-pipe to 0.19 bar (2.7557 psi).	On the ACT: No air flows out of the forward opening of the vent-line. NOTE: If air flows out of the forward opening of the vent-line, it is necessary to do the applicable repair procedure.
3.On the air source: Stop the pressurization.
4.On ACT4.1: Open the forward ACT vent isolation-valve.

5. Close-up
Subtask 28-28-00-410-083-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
(2) Install ACT4.1 in the forward cargo compartment (Ref. AMM D/O 28-11-27-40).

Subtask 28-28-00-860-238-A ** ON A/C NOT FOR ALL

B. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.02 06:17:54 UTC