Avionics Equipment Ventilation Computer Inoperative (AEVC) - Check of the Ventilation System

TASK 21-26-00-040-005-A
Avionics Equipment Ventilation Computer Inoperative (AEVC) - Check of the Ventilation System

Task Summary

Access	Test	Specific Tools	Mhr	E/T	Nb Men
YES	YES	NO	0.3	0.3	1

1. Reason for the Job
MMEL 21-26-10A
AVIONICS EQUIPMENT VENTILATION COMPUTER (AEVC)
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
824

C. Referenced Information

REFERENCE	DESIGNATION
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 31-60-00-860-001-A	EIS Start Procedure
TASK 31-60-00-860-002-A	EIS Stop Procedure
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
Skin Air-Inlet Valve

3. Job Set-up
Subtask 21-26-00-861-073-A

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only)
(Ref. AMM TASK 31-60-00-860-001).

Subtask 21-26-00-010-061-A

B. Get Access
(1) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position at the access door 824.
(2) Open the access door 824 (Ref. AMM TASK 52-41-00-010-002).

4. Procedure
Subtask 21-26-00-040-050-B

A. AEVC Check of Ventilation System and Skin Air-Inlet Valve-Closure

Skin Air-Inlet Valve

(1) Do this test:

ACTION	RESULT
1.On the VENTILATION section of the overhead panel 22VU: Release the BLOWER and EXTRACT pushbutton switches.	On the VENTILATION section of the overhead panel 22VU: The OVRD legends of the BLOWER and EXTRACT pushbutton switches come on.
If the ground horn is activated: On the rear circuit breaker panel 121VU: Open the circuit breaker 2WC. NOTE: The circuit breaker 2WC must be closed again after the first engine start. If the horn is operated after landing when the engines are stopped, it can be deactivated again. Then, you must switch off the ADIRS before you go away from the aircraft.	The ground horn is deactivated.
	On the lower ECAM display unit, on the CAB PRESS page: The outlet valve is partially open. NOTE: If the ventilation system is defective or when the BLOWER and EXTRACT pushbutton switches are released (OVRD legends on): There are no more colored backgrounds on the EFIS displays.
	In the aft avionics compartment: The conditionned air inlet valve 21HQ is open. You can hear the extract fan operate.
	On the CAB PRESS page: The VENT indication is amber.

(2) On the skin air-inlet valve 15HQ:
(a) Push the PUSH latch to release the handle.
(b) Push the handle to engage the switch.
(c) Set the deactivation switch to OFF.
(d) Stow and latch the handle.
(e) Make sure that the skin air-inlet valve is fully closed.
(3) On the lower ECAM display unit, on the CAB PRESS page:

Make sure that there is no XX on the INLET indication.

(4) On the bottom part of the upper ECAM display unit:

The VENT AVNCS SYS FAULT warning comes into view.

Disregard this warning.
On the ECAM control panel:

Push the CLR key.

5. Close-up
Subtask 21-26-00-410-062-A

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 21-26-00-942-078-A

B. Safety Precautions
(1) Put a WARNING NOTICE(S) in the cockpit to tell the crew that the AEVC is deactivated.
(2) Make an entry in the logbook.

Subtask 21-26-00-862-079-A

C. Aircraft Maintenance Configuration
(1) Do the EIS stop procedure
(Ref. AMM TASK 31-60-00-860-002).
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.02 06:10:59 UTC