Detailed Inspection of Demister Drain Hose Connection Area

TASK 21-26-42-210-001-A
Detailed Inspection of Demister Drain Hose Connection Area

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.

WARNING: DO NOT LET THE FILTER TOUCH YOUR SKIN. DO NOT SHAKE OR HIT THE FILTER. DO NOT LET THE FILTER FALL. DO NOT USE COMPRESSED AIR TO CLEAN THE FILTER OR FILTER HOUSING. THIS CAN CAUSE THE INFECTIOUS MATERIAL TO BECOME AIRBORNE. DISCARD THE FILTER IN A PLASTIC DISPOSAL BAG. IF YOU DO NOT OBEY THESE INSTRUCTIONS, INFECTIOUS MATERIAL FROM THE FILTER CAN CAUSE ILLNESS.

WARNING: PUT ALL AIR FILTERS THAT YOU REMOVE FROM THE AIRCRAFT INTO PLASTIC DISPOSAL BAGS. AIR FILTERS CAN CONTAIN INFECTIOUS MATERIALS WHICH CAN CAUSE ILLNESS. OBEY AIRLINE POLICY AND LOCAL HEALTH DEPARTMENT AND LAW ENFORCEMENT REGULATIONS FOR DISPOSAL OF INFECTIOUS MATERIALS.

CAUTION: USE ONLY THE GROUND SERVICE NETWORK TO SUPPLY ELECTRICITY BECAUSE THE AVIONICS VENTILATION SYSTEM IS NOT SERVICEABLE. IF YOU ENERGIZE THE AIRCRAFT ELECTRICAL CIRCUITS WITHOUT THE VENTILATION SYSTEM YOU WILL CAUSE DAMAGE TO ELECTRICAL EQUIPMENT.

ZONE: 120

1. Reason for the Job
Refer to the MPD TASK: 212600-06
DETAILED INSPECTION OF DEMISTER DRAIN HOSE CONNECTION AREA
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	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
120	AVIONICS COMPARTMENT
824

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 24-42-00-862-001-A	De-energize the Ground Service Network Supplied from the External Power
TASK 52-41-00-410-002-A	Close the Avionics Compartment Doors after Access
Filter Assembly (Siphon and Drain Hose) and Ventilation Duct (Drain Hose)

3. Job Set-up
Subtask 21-26-42-861-054-A ** ON A/C NOT FOR ALL

A. Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).

Subtask 21-26-42-941-055-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) On the AIR COND panel 30VU:
(a) Make sure that the APU BLEED, all ENG BLEED and all PACK pushbutton switches are released (the OFF legends are on).
(b) Put a WARNING NOTICE(S) in position to tell persons not to operate these pushbutton switches.
(2) On the HP and LP ground connectors, put a warning notice in position to tell persons not to supply the ground air sources.

Subtask 21-26-42-865-057-A ** ON A/C NOT FOR ALL

C. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AIR COND/AVNCS VENT/CTL	6HQ	D06
49VU	AIR COND/AVNCS VENT/CTL	5HQ	D05
122VU	AIR COND/AVNCS/VENT/MONG	3HQ	Y17
123VU	AVNCS VENT/EXTC/FAN	2HQ	AC04
123VU	AVNCS VENT/BLOWER/FAN	1HQ	AD10

Subtask 21-26-42-010-054-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position at the access door 824.
(2) Open the access door 824.

4. Procedure
Subtask 21-26-42-020-054-D ** ON A/C NOT FOR ALL

A. Removal of the Demister Filter
(1) Turn the seven door fasteners of the filter housing (1) and open the door.
(2) Remove the demister filter (6).

Subtask 21-26-42-210-056-D ** ON A/C NOT FOR ALL

B. Visual Inspection of the Filter Assembly
(1) Do a visual inspection of the filter assembly for signs of impact, distortion and defective welding.
(2) Make sure that the syphon assembly (2) is in the correct condition.
(3) If not, replace it:
(a) Remove the four screws (3) and the four washers (4) from the syphon assembly (2).
(b) Release the upper clamp (5) from the hose of the syphon assembly (2).
(c) Remove the syphon assembly (2) from the filter housing (1).
(d) Put a new syphon assembly (2) in position below the filter housing (1).
(e) Connect the hose of the syphon assembly (2) to the filter housing (1) and safety it with the upper clamp (5).
(f) Install the four washers (4) and the four screws (3) on the syphon assembly (2) and tighten.

Subtask 21-26-42-420-054-D ** ON A/C NOT FOR ALL

C. Installation of the Demister Filter
(1) Put the demister filter (6) in position in the filter housing (1).
(2) Turn and safety the seven door fasteners of the filter housing (1) to close the door.

5. Close-up
Subtask 21-26-42-410-053-A ** ON A/C NOT FOR ALL

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 21-26-42-865-058-A ** ON A/C NOT FOR ALL

B. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AIR COND/AVNCS VENT/CTL	6HQ	D06
49VU	AIR COND/AVNCS VENT/CTL	5HQ	D05
122VU	AIR COND/AVNCS/VENT/MONG	3HQ	Y17
123VU	AVNCS VENT/EXTC/FAN	2HQ	AC04
123VU	AVNCS VENT/BLOWER/FAN	1HQ	AD10

Subtask 21-26-42-862-054-A ** ON A/C NOT FOR ALL

C. De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).

[Rev.10 from 2021] 2026.04.02 06:11:05 UTC