Installation of the Residual Pressure Control Unit

TASK 21-31-35-400-001-A
Installation of the Residual Pressure Control Unit

FIN: 9HL ** ON A/C NOT FOR ALL

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 1M(3 FT)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
811

C. Referenced Information

REFERENCE	DESIGNATION
TASK 21-31-00-710-802-A	Operational Test of the Residual Pressure Control Unit (RPCU)
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
Residual Pressure Control Unit

3. Job Set-up
Subtask 21-31-35-860-050-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Make sure that the ground service network is energized
(Ref. AMM TASK 24-42-00-861-001).

Subtask 21-31-35-865-051-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
122VU	RPCU	4HL	X23

Subtask 21-31-35-010-051-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position at the access door 811.
(2) Make sure that the access door 811 is open.

4. Procedure
Subtask 21-31-35-420-050-A ** ON A/C NOT FOR ALL

A. Installation of the Residual Pressure Control-Unit

Residual Pressure Control Unit ** ON A/C NOT FOR ALL

(1) Clean the component interfaces and the adjacent area.
(2) Do an inspection of the component interfaces and the adjacent area.
(3) Install the control unit (5) on the mounting (1).
(4) Install the washers (6) and the screws (7). Tighten the screws (7).
(5) Put the bonding strap (2) in position and install the screw (4) and the washer (3). Tighten the screw (4).
(6) Remove the CAP-BLANKING from each electrical connector and receptacle.
(7) Make sure that all the electrical connections are clean and in the correct condition.
(8) Connect the electrical connectors (8) and (9) to the control unit (5).

Subtask 21-31-35-865-052-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
122VU	RPCU	4HL	X23

Subtask 21-31-35-710-050-A ** ON A/C NOT FOR ALL

C. Do the operational test of the residual pressure control-unit (Ref. AMM TASK 21-31-00-710-802).

NOTE: The outflow valve opens automatically during the operational test in the manual mode.

5. Close-up
Subtask 21-31-35-410-050-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) Close the access door 811.
(3) Remove the access platform(s).

Subtask 21-31-35-862-050-A ** ON A/C NOT FOR ALL

B. De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).

[Rev.10 from 2021] 2026.04.02 06:11:15 UTC