DOC AIRBUS | AMM A320FAvionics Ventilation Filter Inoperative - Do the Deactivation of the Conditioned-Air Inlet Valve
TASK 21-26-00-040-017-A
Avionics Ventilation Filter Inoperative - Do the Deactivation of the Conditioned-Air Inlet Valve
MMEL 21-26-09C
AVIONICS VENTILATION FILTER
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 21-26-00-861-093-A
Subtask 21-26-00-040-073-A
Subtask 21-26-00-410-094-A
[Rev.10 from 2021]
2026.04.02 06:11:00 UTC
Avionics Ventilation Filter Inoperative - Do the Deactivation of the Conditioned-Air Inlet Valve
Task Summary
1. Reason for the Job| Access | Test | Specific Tools | Mhr | E/T | Nb Men |
|---|---|---|---|---|---|
| YES | YES | NO | 0.6 | 0.6 | 1 |
MMEL 21-26-09C
AVIONICS VENTILATION FILTER
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 | AR | CAP - BLANKING |
| No specific | AR | SAFETY CLIP - CIRCUIT BREAKER |
| No specific | AR | WARNING NOTICE(S) |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 824 |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 21-26-00-710-001-A | Operational Check of the Avionics Equipment Ventilation-System via MCDU |
| TASK 21-26-00-710-001-A-01 | Operational Check of the Avionics Equipment Ventilation (without the CFDS) |
| 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 |
Air-Conditioned Inlet ValveSubtask 21-26-00-861-093-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 21-26-00-865-107-A (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).
B. Open, safety and tag this(these) circuit breaker(s):
Subtask 21-26-00-010-097-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| 49VU | AIR COND/AVNCS VENT/CTL | 5HQ | D05 |
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).
4. Procedure(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 21-26-00-040-073-A
A. Opening Procedure of the Conditioned-Air Inlet Valve
(1) On the VENTILATION section of the overhead control and indicating panel 22VU:
(a) Disconnect the connector 21HQ-A from the conditioned-air inlet valve 21HQ.
(b) Put CAP - BLANKING on the disconnected electrical connectors.
(c) Keep the electrical cable and its connector near the valve.
(d) Fully open the conditioned-air inlet valve 21HQ with the manual mechanism.
(3) On the bottom part of the upper ECAM display unit:
On the ECAM control panel:
Subtask 21-26-00-865-111-A (1) On the VENTILATION section of the overhead control and indicating panel 22VU:
- Release the EXTRACT pushbutton switch (the OVRD legend comes on).
(a) Disconnect the connector 21HQ-A from the conditioned-air inlet valve 21HQ.
(b) Put CAP - BLANKING on the disconnected electrical connectors.
(c) Keep the electrical cable and its connector near the valve.
(d) Fully open the conditioned-air inlet valve 21HQ with the manual mechanism.
(3) On the bottom part of the upper ECAM display unit:
- The VENT AVNCS SYS FAULT warning comes into view.
On the ECAM control panel:
- Push the CLR key.
B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
Subtask 21-26-00-710-086-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| 49VU | AIR COND/AVNCS VENT/CTL | 5HQ | D05 |
C. Do the Operational Test:
5. Close-upCAUTION:
AFTER THE DEACTIVATION OF THE APPLICABLE VALVE, MAKE SURE THAT YOU DO THE OPERATIONAL TEST OF THE AVIONICS-EQUIPMENT VENTILATION-SYSTEM BEFORE EACH FLIGHT.
(1) Do an operational test of the avionics equipment ventilation from the Multipurpose Control and Display Unit (MCDU) (Ref. AMM TASK 21-26-00-710-001). NOTE: Make sure that all the fault messages shown are related to:
- The fault of the ventilation filter, and
- The deactivation of the conditioned-air inlet valve (21HQ).
If other messages are shown, refer to the related MMEL valve item.
Subtask 21-26-00-410-094-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 21-26-00-942-091-A (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).
B. Safety Precautions
(1) Put a WARNING NOTICE(S) in position in the cockpit to tell the crew that the avionics ventilation filter and the conditioned-air inlet valve are deactivated.
(2) Make an entry in the logbook.
Subtask 21-26-00-862-096-A (1) Put a WARNING NOTICE(S) in position in the cockpit to tell the crew that the avionics ventilation filter and the conditioned-air inlet valve are deactivated.
(2) Make an entry in the logbook.
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).
(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).