DOC AIRBUS | AMM A320FInstallation of the Lower Part of the Mixer Unit
TASK 21-21-43-400-003-A
Installation of the Lower Part of the Mixer Unit
Do this task to close the access to the Pressure Bulkhead at FR35 FWD Face as requested by MPD task 533152-01.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Expendable Parts
E. Referenced Information
3. Job Set-up
Subtask 21-21-43-860-054-A
Subtask 21-21-43-560-051-A
Subtask 21-21-43-410-052-A
[Rev.10 from 2021]
2026.04.02 07:25:04 UTC
Installation of the Lower Part of the Mixer Unit
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 PNEUMATIC SYSTEM IS DEPRESSURIZED BEFORE YOU START WORK. PRESSURIZED AIR CAN CAUSE INJURY TO PERSONNEL.
WARNING:
DO NOT TOUCH THE COMPONENT UNTIL IT IS SUFFICIENTLY
COOL TO PREVENT BURNS.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
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.
CAUTION:
DO NOT PUT YOUR WEIGHT ON THE DUCTS. IT IS VERY EASY TO BREAK THEM.
ZONE: 130
1. Reason for the JobDo this task to close the access to the Pressure Bulkhead at FR35 FWD Face as requested by MPD task 533152-01.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | ACCESS PLATFORM 2M (6 FT) |
| No specific | 1 | SCRAPER - PLASTIC |
| No specific | AR | WARNING NOTICE(S) |
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.14SBA1) | Textile-Lint free Cotton - |
| No specific | soap solution |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 130 | FWD CARGO COMPT AFT BULKHEAD OF AVNCS COMPT TO FWD PRESSURE BULKHEAD OF WING CENTER BOX |
| 825 |
| FIG.ITEM | DESIGNATION | IPC-CSN |
|---|---|---|
| 12 | SEAL | AIPC 21-21-43-02-020 |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 12-33-21-618-001-A-01 | Pre-conditioning through the HP Ground Connection |
| TASK 12-33-21-618-001-A-02 | Pre-conditioning with the APU |
| 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 06-41-53-00 | FUSELAGE-DESCRIPTION AND OPERATION |
Lower Part of the Mixer UnitSubtask 21-21-43-860-054-A
A. Aircraft Maintenance Configuration
(1) Make sure that:
(a) The aircraft electrical circuits are energized (Ref. AMM TASK 24-41-00-861-002).
(b) On the overhead panel, on panel 30VU:
1 The APU BLEED pushbutton switch is in the off position (the ON legend is off).
2 The ENG 1 BLEED and the ENG 2 BLEED pushbutton switches are in the off position (the OFF legends are on).
3 The PACK 1 and the PACK 2 pushbutton switches are in the off position (the OFF legends are on).
4 The HOT AIR pushbutton switch is in the off position (the OFF legend is on).
5 The WARNING NOTICE(S) is (are) in position to tell persons not to operate these switches.
(c) On the HP and the LP ground connectors the WARNING NOTICE(S) is (are) in position to tell persons not to supply ground air.
Subtask 21-21-43-010-053-A (1) Make sure that:
(a) The aircraft electrical circuits are energized (Ref. AMM TASK 24-41-00-861-002).
(b) On the overhead panel, on panel 30VU:
1 The APU BLEED pushbutton switch is in the off position (the ON legend is off).
2 The ENG 1 BLEED and the ENG 2 BLEED pushbutton switches are in the off position (the OFF legends are on).
3 The PACK 1 and the PACK 2 pushbutton switches are in the off position (the OFF legends are on).
4 The HOT AIR pushbutton switch is in the off position (the OFF legend is on).
5 The WARNING NOTICE(S) is (are) in position to tell persons not to operate these switches.
(c) On the HP and the LP ground connectors the WARNING NOTICE(S) is (are) in position to tell persons not to supply ground air.
B. Get Access
(1) Make sure that:
(a) Forward cargo-compartment door 825 is open (Ref. AMM TASK 52-30-00-860-001).
(b) The ACCESS PLATFORM 2M (6 FT) is in position at forward cargo-compartment door 825.
(c) The access panels at partition FR 34 are removed (Ref. AMM D/O 06-41-53-00) (Ref. AMM TASK 25-54-12-000-001).
Subtask 21-21-43-865-054-A (1) Make sure that:
(a) Forward cargo-compartment door 825 is open (Ref. AMM TASK 52-30-00-860-001).
(b) The ACCESS PLATFORM 2M (6 FT) is in position at forward cargo-compartment door 825.
(c) The access panels at partition FR 34 are removed (Ref. AMM D/O 06-41-53-00) (Ref. AMM TASK 25-54-12-000-001).
C. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:
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/FLOW/MIXER/FLAP | 3HB | V22 |
| 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 ALL | |||
| 122VU | AIR COND/RECIRC FAN/R/CTL | 11HG | W20 |
| 122VU | AIR COND/RECIRC FAN/R/SPLY | 3HG | W18 |
| 122VU | AIR COND/RECIRC FAN/L/CTL | 2HG | X20 |
| 122VU | AIR COND/RECIRC FAN/L/SPLY | 1HG | X18 |
| ** 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 21-21-43-560-051-A
A. Preparation for Installation of the Lower Part of the Mixer Unit
(1) Remove the blanking plugs from the lower part of the mixer unit (8).
(2) Use a SCRAPER - PLASTIC and remove the remaining seal (12) from the flange of the lower part of the mixer unit (8).
(3) Clean the component interfaces and the adjacent area.
(4) Do an inspection of the component interfaces and the adjacent area.
Subtask 21-21-43-420-053-A (1) Remove the blanking plugs from the lower part of the mixer unit (8).
(2) Use a SCRAPER - PLASTIC and remove the remaining seal (12) from the flange of the lower part of the mixer unit (8).
(3) Clean the component interfaces and the adjacent area.
(4) Do an inspection of the component interfaces and the adjacent area.
B. Installation of the Lower Part of the Mixer Unit
(1) Make sure that the parts retained from the removed component are clean and in the correct condition.
(2) Remove the blanking plugs from the upper part of the mixer unit (14).
(3) Remove the blanking plugs from the sleeves (2) and (6).
(4) Make sure that the ducts are clean and that there are no blockages.
(5) Put the new AIPC 21-21-43-02-020 SEAL (12) on the flange of the lower part of the mixer unit (8).
(6) Put the lower part of the mixer unit (8) in position and loosely attach it to the aircraft structure with the washers (5) and the bolts (4).
(7) Do not tighten the bolts (4) at this time.
(8) Put the lower part of the mixer unit (8) in position below the upper part of the mixer unit (14).
(9) Install the bolts (13), the washers (11) and the nuts (10).
(10) Tighten the nuts (10).
(11) Put the tie rod (16) in position on the lower part of the mixer unit (8).
(12) If necessary, adjust the length of the tie rod (16).
(13) Install the washers (18), the bolt (19) and the nut (17).
(14) Tighten the nut (17).
(15) Move the sleeves (2) and (6) into position on the flanges of the lower part of the mixer unit (8).
(17) Make sure that the mixer unit is in the correct position.
(18) Tighten the bolts (4).
(19) Remove the CAP-BLANKING from each electrical connector and receptacle.
(21) Connect the electrical connectors (1), (9) and (15).
(22) Make sure that the work area is clean and clear of tools and other items.
Subtask 21-21-43-865-055-A (1) Make sure that the parts retained from the removed component are clean and in the correct condition.
(2) Remove the blanking plugs from the upper part of the mixer unit (14).
(3) Remove the blanking plugs from the sleeves (2) and (6).
(4) Make sure that the ducts are clean and that there are no blockages.
(5) Put the new AIPC 21-21-43-02-020 SEAL (12) on the flange of the lower part of the mixer unit (8).
(6) Put the lower part of the mixer unit (8) in position and loosely attach it to the aircraft structure with the washers (5) and the bolts (4).
(7) Do not tighten the bolts (4) at this time.
(8) Put the lower part of the mixer unit (8) in position below the upper part of the mixer unit (14).
(9) Install the bolts (13), the washers (11) and the nuts (10).
(10) Tighten the nuts (10).
(11) Put the tie rod (16) in position on the lower part of the mixer unit (8).
(12) If necessary, adjust the length of the tie rod (16).
(13) Install the washers (18), the bolt (19) and the nut (17).
(14) Tighten the nut (17).
(15) Move the sleeves (2) and (6) into position on the flanges of the lower part of the mixer unit (8).
NOTE: You cannot see the color markings on the flanges if the sleeves are installed correctly.
(16) Install the clamps (3) and (7). (17) Make sure that the mixer unit is in the correct position.
(18) Tighten the bolts (4).
(19) Remove the CAP-BLANKING from each electrical connector and receptacle.
CAUTION:
MAKE SURE THAT THE ELECTRICAL CONNECTORS ARE CLEAN BEFORE YOU DISCONNECT OR CONNECT THEM. CONTAMINATION ON THE ELECTRICAL CONNECTORS CAN CAUSE DAMAGE TO EQUIPMENT.
(20) Make sure that all the electrical connections are clean and in the correct condition.(21) Connect the electrical connectors (1), (9) and (15).
(22) Make sure that the work area is clean and clear of tools and other items.
C. Make sure that this(these) circuit breaker(s) is(are) closed:
Subtask 21-21-43-710-051-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 49VU | AIR COND/FLOW/CTL &/IND1 | 1HB | D07 |
| ** 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/FLOW/MIXER/FLAP | 3HB | V22 |
| 122VU | AIR COND/FLOW/CTL AND IND/2 | 2HB | V21 |
| 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 |
| 122VU | AIR COND/PACK TEMP/CTL SYS1/2/115VAC | 21HH | W22 |
| 122VU | AIR COND/PACK TEMP/CTL SYS1/2/28VDC | 23HH | W21 |
| 122VU | AIR COND/PACK TEMP/CTL SYS1/1/115VAC | 1HH | X22 |
| 122VU | AIR COND/PACK TEMP/CTL SYS1/1/28VDC | 3HH | X21 |
| 122VU | AIR COND/PACK TEMP CTL SYS2/2/28VDC | 24HH | Y21 |
| 122VU | AIR COND/PACK TEMP CTL SYS2/2/115VAC | 22HH | Y20 |
| 122VU | AIR COND/PACK TEMP CTL SYS2/1/28VDC | 4HH | Y19 |
| 122VU | AIR COND/PACK TEMP CTL SYS2/1/115VAC | 2HH | Y18 |
| ** ON A/C ALL | |||
| 122VU | AIR COND/RECIRC FAN/R/CTL | 11HG | W20 |
| 122VU | AIR COND/RECIRC FAN/R/SPLY | 3HG | W18 |
| 122VU | AIR COND/RECIRC FAN/L/CTL | 2HG | X20 |
| 122VU | AIR COND/RECIRC FAN/L/SPLY | 1HG | X18 |
| ** 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 |
D. Test
(1) Do the pre-conditioning through the HP ground connector (Ref. AMM TASK 12-33-21-618-001) or with the APU (Ref. AMM TASK 12-33-21-618-001).
(2) Do a leak check of the mixer unit and the mixer unit duct connections:
(a) Apply soap solution to all the applicable connections.
(b) Examine the connections for leaks.
(c) Make sure that there are no leaks.
(d) Remove the soap solution with a Textile-Lint free Cotton - (Material No.14SBA1) from all the connections.
(3) Make sure that the recirculation fans operate correctly.
(4) After approximately 15 minutes, stop the pre-conditioning (Ref. AMM TASK 12-33-21-618-001) or (Ref. AMM TASK 12-33-21-618-001).
5. Close-up(1) Do the pre-conditioning through the HP ground connector (Ref. AMM TASK 12-33-21-618-001) or with the APU (Ref. AMM TASK 12-33-21-618-001).
(2) Do a leak check of the mixer unit and the mixer unit duct connections:
(a) Apply soap solution to all the applicable connections.
(b) Examine the connections for leaks.
(c) Make sure that there are no leaks.
(d) Remove the soap solution with a Textile-Lint free Cotton - (Material No.14SBA1) from all the connections.
(3) Make sure that the recirculation fans operate correctly.
(4) After approximately 15 minutes, stop the pre-conditioning (Ref. AMM TASK 12-33-21-618-001) or (Ref. AMM TASK 12-33-21-618-001).
Subtask 21-21-43-410-052-A
A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the access panels at partition FR34 (Ref. AMM D/O 06-41-53-00), (Ref. AMM TASK 25-54-12-400-001).
(3) Remove the access platform(s).
(4) Close the FWD cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-002).
(5) Remove the WARNING NOTICE(S).
Subtask 21-21-43-862-051-A (1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the access panels at partition FR34 (Ref. AMM D/O 06-41-53-00), (Ref. AMM TASK 25-54-12-400-001).
(3) Remove the access platform(s).
(4) Close the FWD cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-002).
(5) Remove the WARNING NOTICE(S).