DOC AIRBUS | AMM A320FDeactivation of the Hot-Air Pressure-Regulating Valve
TASK 21-63-00-040-002-A
Deactivation of the Hot-Air Pressure-Regulating Valve
MMEL 21-63-03C
HOT AIR PRESSURE REGULATING VALVE
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 21-63-00-861-052-A Subtask 21-63-00-941-062-A
Subtask 21-63-00-040-053-A ** ON A/C NOT FOR ALL
Subtask 21-63-00-410-051-A
[Rev.10 from 2021]
2026.04.02 06:11:42 UTC
Deactivation of the Hot-Air Pressure-Regulating Valve
WARNING:
MAKE SURE THAT AIR IS NOT SUPPLIED TO THE AIR CONDITIONING SYSTEM FROM THE MAIN ENGINE, THE APU OR A GROUND SOURCE.
HOT COMPRESSED AIR CAN CAUSE INJURY TO PERSONNEL.
WARNING:
MAKE SURE THAT THE COMPONENTS OF THE BLEED AIR SYSTEM ARE COOL. HOT COMPONENTS WILL BURN YOU.
CAUTION:
BE VERY CAREFUL WHEN YOU DO WORK ON OR NEAR THE AIR-CONDITIONING DUCTS. THE DUCTS ARE MADE OF THIN MATERIAL AND YOU CAN EASILY BREAK THEM.
1. Reason for the JobMMEL 21-63-03C
HOT AIR PRESSURE REGULATING VALVE
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE |
| No specific | AR | CAP - BLANKING |
| No specific | AR | SAFETY CLIP - CIRCUIT BREAKER |
| No specific | AR | WARNING NOTICE(S) |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 191CB, 191DB, 825 |
| 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 25-54-12-000-001-A | Removal of the Forward Cargo-Compartment Partition |
| TASK 25-54-12-400-001-A | Installation of the Forward Cargo-Compartment Partition |
| TASK 52-30-00-860-001-A | Open the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump |
| TASK 52-30-00-860-002-A | Close the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump |
| TASK 52-30-00-860-003-A | Open the FWD or Aft Cargo-Compartment Door with the Hand Pump |
| TASK 52-30-00-860-004-A | Close the FWD or Aft Cargo-Compartment Door with the Hand Pump |
Hot-Air Pressure-Regulating ValveSubtask 21-63-00-861-052-A Subtask 21-63-00-941-062-A
B. Safety Precautions
(1) In the cockpit, on AIR COND panel 30VU:
(a) Make sure that the APU BLEED pushbutton switch is released (the OFF legend is on).
(b) Make sure that the ENG 1 BLEED and the ENG 2 BLEED pushbutton switches are released (the OFF legends are on).
(c) Make sure that the PACK 1 and the PACK 2 pushbutton switches are released (the OFF legends are on).
(d) Make sure that the HOT AIR pushbutton switch is released (the OFF legend is on).
(e) Put the WARNING NOTICE(S) in position to tell persons not to operate these pushbutton switches.
(2) At access doors 191CB and 191DB:
(a) On the LP and the HP ground connectors, put the WARNING NOTICE(S) in position to tell persons not to supply the ground air.
Subtask 21-63-00-010-051-A (1) In the cockpit, on AIR COND panel 30VU:
(a) Make sure that the APU BLEED pushbutton switch is released (the OFF legend is on).
(b) Make sure that the ENG 1 BLEED and the ENG 2 BLEED pushbutton switches are released (the OFF legends are on).
(c) Make sure that the PACK 1 and the PACK 2 pushbutton switches are released (the OFF legends are on).
(d) Make sure that the HOT AIR pushbutton switch is released (the OFF legend is on).
(e) Put the WARNING NOTICE(S) in position to tell persons not to operate these pushbutton switches.
(2) At access doors 191CB and 191DB:
(a) On the LP and the HP ground connectors, put the WARNING NOTICE(S) in position to tell persons not to supply the ground air.
C. Get Access
(2) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position at forward cargo-compartment door 825.
(3) Remove the access panel from partition FR 34 (Ref. AMM TASK 25-54-12-000-001).
Subtask 21-63-00-865-054-A WARNING:
DO NOT OPEN OR GO NEAR PRESSURE-SEALED DOORS WHEN THE AIRCRAFT IS PRESSURIZED.
A PRESSURE-SEALED DOOR THAT OPENS WHEN THE AIRCRAFT IS PRESSURIZED:
(1) Open forward cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-001) or (Ref. AMM TASK 52-30-00-860-003).- WILL CAUSE EXPLOSIVE DECOMPRESSION.
- CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAUSE DAMAGE TO THE AIRCRAFT OR EQUIPMENT.
(2) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position at forward cargo-compartment door 825.
(3) Remove the access panel from partition FR 34 (Ref. AMM TASK 25-54-12-000-001).
D. Open, safety and tag this(these) circuit breaker(s):
4. Procedure| PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 49VU | AIR COND/TEMP CTL/SYS 1 CHAN B/28VDC | 52HH | D08 |
| ** ON A/C NOT FOR ALL | |||
| 122VU | AIR COND/ZONE TEMP CTL/28VDC/SYS2 | 4HK | V20 |
| 122VU | AIR COND/ZONE TEMP CTL/28VDC/SYS1 | 3HK | V19 |
| 122VU | AIR COND/ZONE TEMP CTL/115VAC/SYS2 | 2HK | V18 |
| 122VU | AIR COND/ZONE TEMP CTL/115VAC/SYS1 | 1HK | V17 |
| ** ON A/C NOT FOR ALL | |||
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN A/115VAC | 53HH | W22 |
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN A/28VDC | 55HH | W21 |
| 122VU | AIR COND/TEMP CTL SYS 1/CHAN A/115VAC | 49HH | X22 |
| 122VU | AIR COND/TEMP CTL SYS 1/CHAN A/28VDC | 51HH | X21 |
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN B/28VDC | 56HH | Y21 |
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN B/115VAC | 54HH | Y20 |
| 122VU | AIR COND/TEMP CTL SYS 1/CHAN B/115VAC | 50HH | Y18 |
Subtask 21-63-00-040-053-A ** ON A/C NOT FOR ALL
A. Deactivation of the Pressure Regulating Valve
(1) Turn the manual override lever (3) to the closed position.
(2) Disconnect the electrical connector 14HK-C (1) from the pressure regulating valve (2).
(3) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(4) Temporarily attach the disconnected electrical connector 14HK-C (1) to the aircraft structure.
Subtask 21-63-00-040-053-B ** ON A/C NOT FOR ALL (1) Turn the manual override lever (3) to the closed position.
(2) Disconnect the electrical connector 14HK-C (1) from the pressure regulating valve (2).
(3) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(4) Temporarily attach the disconnected electrical connector 14HK-C (1) to the aircraft structure.
A. Deactivation of the Pressure Regulating Valve (new ECS)
(1) Turn the manual override lever (3) to the closed position.
(2) Disconnect the electrical connector 14HK-A (1) from the pressure regulating valve (2).
(3) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(4) Temporarily attach the disconnected electrical connector 14HK-A (1) to the aircraft structure.
5. Close-up(1) Turn the manual override lever (3) to the closed position.
(2) Disconnect the electrical connector 14HK-A (1) from the pressure regulating valve (2).
(3) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(4) Temporarily attach the disconnected electrical connector 14HK-A (1) to the aircraft structure.
Subtask 21-63-00-410-051-A
A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the access panel at partition FR 34 (Ref. AMM TASK 25-54-12-400-001).
(3) Remove the access platform(s).
(4) Close forward cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-002) or (Ref. AMM TASK 52-30-00-860-004).
(5) Put an applicable placard in position in the cockpit (refer to your standard practices and local regulations).
(6) Remove the WARNING NOTICE(S).
(7) Make an entry in the logbook.
Subtask 21-63-00-865-065-A (1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the access panel at partition FR 34 (Ref. AMM TASK 25-54-12-400-001).
(3) Remove the access platform(s).
(4) Close forward cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-002) or (Ref. AMM TASK 52-30-00-860-004).
(5) Put an applicable placard in position in the cockpit (refer to your standard practices and local regulations).
(6) Remove the WARNING NOTICE(S).
(7) Make an entry in the logbook.
B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
Subtask 21-63-00-862-051-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 49VU | AIR COND/TEMP CTL/SYS 1 CHAN B/28VDC | 52HH | D08 |
| ** ON A/C NOT FOR ALL | |||
| 122VU | AIR COND/ZONE TEMP CTL/28VDC/SYS2 | 4HK | V20 |
| 122VU | AIR COND/ZONE TEMP CTL/28VDC/SYS1 | 3HK | V19 |
| 122VU | AIR COND/ZONE TEMP CTL/115VAC/SYS2 | 2HK | V18 |
| 122VU | AIR COND/ZONE TEMP CTL/115VAC/SYS1 | 1HK | V17 |
| ** ON A/C NOT FOR ALL | |||
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN A/115VAC | 53HH | W22 |
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN A/28VDC | 55HH | W21 |
| 122VU | AIR COND/TEMP CTL SYS 1/CHAN A/115VAC | 49HH | X22 |
| 122VU | AIR COND/TEMP CTL SYS 1/CHAN A/28VDC | 51HH | X21 |
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN B/28VDC | 56HH | Y21 |
| 122VU | AIR COND/TEMP CTL SYS 2/CHAN B/115VAC | 54HH | Y20 |
| 122VU | AIR COND/TEMP CTL SYS 1/CHAN B/115VAC | 50HH | Y18 |