Operational Check of NRV for Free Movement

TASK 21-26-43-710-001-A
Operational Check of NRV for Free Movement

ZONE: 120

1. Reason for the Job
Refer to the MPD TASK: 212643-09
OPERATIONAL CHECK OF NRV FOR FREE MOVEMENT
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
120	AVIONICS COMPARTMENT
824

C. Referenced Information

REFERENCE	DESIGNATION
TASK 21-26-43-100-001-A	Inspection of the Siphon Assembly (Strainer) for Cleanliness
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
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 52-41-00-010-002-A	Open the Avionics Compartment Doors for Access
TASK 52-41-00-410-002-A	Close the Avionics Compartment Doors after Access
Check Valve of the Avionics Ventillation Water / Dust Separation ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 21-26-43-865-087-A ** ON A/C NOT FOR ALL

A. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AIR COND/AVNCS VENT/CTL	6HQ	D06
49VU	AIR COND/AVNCS VENT/CTL	5HQ	D05
122VU	AIR COND/AVNCS/VENT/MONG	3HQ	Y17
** ON A/C NOT FOR ALL
123VU	AVNCS VENT/EXTC/FAN	2HQ	AE02
** ON A/C NOT FOR ALL
123VU	AVNCS VENT/BLOWER/FAN	1HQ	AD10
** ON A/C NOT FOR ALL
123VU	AVNCS VENT/EXTC/FAN	2HQ	AC04

Subtask 21-26-43-941-067-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) Make sure that the throttle control levers of the engines 1 and 2 are at idle.

Subtask 21-26-43-010-099-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position at the access door 824.
(2) Open the access door 824 (Ref. AMM TASK 52-41-00-010-002).

Subtask 21-26-43-861-086-A ** ON A/C NOT FOR ALL

D. Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).

Subtask 21-26-43-860-055-A ** ON A/C NOT FOR ALL

E. Aircraft Maintenance Configuration
(1) On the VENTILATION section of the panel 22VU:

make sure that the BLOWER and EXTRACT pushbutton switches are in the AUTO configuration (pushed and with the FAULT and OVRD legends off).

4. Procedure
Subtask 21-26-43-710-054-A ** ON A/C NOT FOR ALL

A. Operational Test of the Check Valve of the Syphon Assembly

NOTE: The energization of the aircraft electrical circuits starts a full test of the ventilation system. The test continues for 2 minutes approximately.

(1) Make sure that the bowl of the syphon is clean.
(a) If there are debris, clean the syphon assembly (Ref. AMM TASK 21-26-43-100-001).
(2) Make sure that the ball of the check valve moves up.
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

Subtask 21-26-43-861-090-A ** ON A/C NOT FOR ALL

B. Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001)
(1) Make sure that the ball of the check valve moves down.

5. Close-up
Subtask 21-26-43-410-092-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 824 (Ref. AMM TASK 52-41-00-410-002).
(3) Remove the access platform(s).

Subtask 21-26-43-862-086-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 06:11:06 UTC