Installation of the Recirculation Filter Cartridge
TASK 21-21-41-400-001-A
Installation of the Recirculation Filter Cartridge
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Expendable Parts
D. Referenced Information
3. Job Set-up
Subtask 21-21-41-860-050-A
Subtask 21-21-41-420-055-A
Subtask 21-21-41-410-051-A
[Rev.10 from 2021]
2026.04.01 04:09:12 UTC
Installation of the Recirculation Filter Cartridge
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:
PUT ON GLOVES, A COVERALL WITH A HOOD, GOGGLES AND A PARTICULATE RESPIRATOR BEFORE YOU TOUCH THE FILTER. THE FILTER REMOVES SMALL PARTICLES (SMOKE, DUST, LINT, FIBERS, POLLEN) AND INFECTIOUS MATERIALS (BACTERIA, VIRUSES, MOLD SPORES, FUNGI) FROM THE AIR. THESE MATERIALS CAN CAUSE ILLNESS.
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.
NOTE: The procedure is the same for the recirculation filter cartridges 4012HM and 4013HM.
1. Reason for the JobSelf explanatory
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 | WARNING NOTICE(S) |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 130 | FWD CARGO COMPT AFT BULKHEAD OF AVNCS COMPT TO FWD PRESSURE BULKHEAD OF WING CENTER BOX |
| 191CB, 191DB, 825 |
| FIG.ITEM | DESIGNATION | IPC-CSN |
|---|---|---|
| 3 | CARTRIDGE | AIPC 21-21-02-49-020 |
| 3 | CARTRIDGE | AIPC 21-21-82-44-100 |
| 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 |
Subtask 21-21-41-860-050-A
A. Aircraft Maintenance Configuration
(1) Make sure that the aircraft electrical circuits are energized
(Ref. AMM TASK 24-41-00-861-002).
(2) In the cockpit, on the 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) Make sure that the WARNING NOTICE(S) are in position to tell persons not to operate these switches.
(3) At access doors 191CB and 191DB:
(a) Make sure that the WARNING NOTICE(S) are in position on the HP and the LP ground connectors to tell persons not to supply ground air.
(4) Make sure that forward cargo-compartment door 825 is open (Ref. AMM TASK 52-30-00-860-001) or (Ref. AMM TASK 52-30-00-860-003).
(5) Make sure that the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE is in position below the forward cargo-compartment door 825.
(6) Make sure that the access panel is removed from partition FR 34 or FR 35.7 (Ref. AMM TASK 25-54-12-000-001).
Subtask 21-21-41-865-051-A (1) Make sure that the aircraft electrical circuits are energized
(Ref. AMM TASK 24-41-00-861-002).
(2) In the cockpit, on the 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) Make sure that the WARNING NOTICE(S) are in position to tell persons not to operate these switches.
(3) At access doors 191CB and 191DB:
(a) Make sure that the WARNING NOTICE(S) are in position on the HP and the LP ground connectors to tell persons not to supply ground air.
(4) Make sure that forward cargo-compartment door 825 is open (Ref. AMM TASK 52-30-00-860-001) or (Ref. AMM TASK 52-30-00-860-003).
(5) Make sure that the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE is in position below the forward cargo-compartment door 825.
(6) Make sure that the access panel is removed from partition FR 34 or FR 35.7 (Ref. AMM TASK 25-54-12-000-001).
B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:
4. Procedure| PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| FOR FIN: 4012HM (RECIRC FILTER CARTRIDGE 1) | |||
| 122VU | AIR COND/RECIRC FAN/L/CTL | 2HG | X20 |
| 122VU | AIR COND/RECIRC FAN/L/SPLY | 1HG | X18 |
| FOR FIN: 4013HM (RECIRC FILTER CARTRIDGE 2) | |||
| 122VU | AIR COND/RECIRC FAN/R/CTL | 11HG | W20 |
| 122VU | AIR COND/RECIRC FAN/R/SPLY | 3HG | W18 |
Subtask 21-21-41-420-055-A
A. Installation of the Recirculation Filter Cartridge
(1) Do a visual inspection of the component interfaces and the adjacent area.
(2) Clean the component interfaces and the adjacent area.
(3) Remove the PLUG-BLANKING from each disconnected line end.
(4) Put a new AIPC 21-21-02-49-020 CARTRIDGE (3) or AIPC 21-21-82-44-100 CARTRIDGE (3) in position in the recirculation filter housing (1):
(a) For the recirculation filter housing (1), part number 34800B200-1:
1 Push the fastener (2) and turn it clockwise to the LOCKED position.
(b) For the recirculation filter housing (1), part number QB0658 series:
1 Turn the lever (2) clockwise to lock the recirculation filter cartridge (3).
(5) Make sure that the work area is clean and clear of tools and other items.
5. Close-up(1) Do a visual inspection of the component interfaces and the adjacent area.
(2) Clean the component interfaces and the adjacent area.
(3) Remove the PLUG-BLANKING from each disconnected line end.
(4) Put a new AIPC 21-21-02-49-020 CARTRIDGE (3) or AIPC 21-21-82-44-100 CARTRIDGE (3) in position in the recirculation filter housing (1):
(a) For the recirculation filter housing (1), part number 34800B200-1:
1 Push the fastener (2) and turn it clockwise to the LOCKED position.
(b) For the recirculation filter housing (1), part number QB0658 series:
1 Turn the lever (2) clockwise to lock the recirculation filter cartridge (3).
(5) Make sure that the work area is clean and clear of tools and other items.
Subtask 21-21-41-410-051-A
A. Close Access
(1) Install the access panel at partition FR 34 or FR 35.7 (Ref. AMM TASK 25-54-12-400-001).
(2) Remove the access platform(s).
(3) Close forward cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-002) or (Ref. AMM TASK 52-30-00-860-004).
(4) Remove the WARNING NOTICE(S).
Subtask 21-21-41-865-052-A (1) Install the access panel at partition FR 34 or FR 35.7 (Ref. AMM TASK 25-54-12-400-001).
(2) Remove the access platform(s).
(3) Close forward cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-002) or (Ref. AMM TASK 52-30-00-860-004).
(4) Remove the WARNING NOTICE(S).
B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
Subtask 21-21-41-862-050-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| FOR FIN: 4012HM (RECIRC FILTER CARTRIDGE 1) | |||
| 122VU | AIR COND/RECIRC FAN/L/CTL | 2HG | X20 |
| 122VU | AIR COND/RECIRC FAN/L/SPLY | 1HG | X18 |
| FOR FIN: 4013HM (RECIRC FILTER CARTRIDGE 2) | |||
| 122VU | AIR COND/RECIRC FAN/R/CTL | 11HG | W20 |
| 122VU | AIR COND/RECIRC FAN/R/SPLY | 3HG | W18 |
Recirculation Filter Cartridge