Removal of the Tube of the Potable Water and the associated Air Supply System

TASK 20-23-38-000-001-A
Removal of the Tube of the Potable Water and the associated Air Supply System

WARNING: DO NOT DO WORK ON THE TOILET WASTE SYSTEM AND THE POTABLE WATER SYSTEM AT THE SAME TIME. THIS WILL PREVENT CONTAMINATION OF THE POTABLE WATER SYSTEM. SUCH CONTAMINATION CAN BE DANGEROUS TO HEALTH.

WARNING: MAKE SURE THAT THE POTABLE WATER SYSTEM IS DEPRESSURIZED. A PRESSURIZED SYSTEM CAN CAUSE INJURY TO PERSONS WHEN THEY DO WORK ON IT.

WARNING: MAKE SURE THAT THE EQUIPMENT YOU USE FOR THIS PROCEDURE IS CLEAN AND APPROVED FOR THE POTABLE WATER SYSTEM. IF NOT IT CAN CAUSE CONTAMINATION OF THE POTABLE WATER SYSTEM.

NOTE: The procedure is the same for both the potable and the air supply system.

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	3	CONTAINER - CLEAN, APPLICABLE
No specific	2	CONTAINER 1 L (1/4 USGAL)
No specific	AR	CUTTER - ROLLER TYPE, CHIPLESS
No specific	AR	PLUG - BLANKING
No specific	1	SCRAPER - NON METALLIC
No specific	AR	WARNING NOTICE(S)

B. Referenced Information

REFERENCE	DESIGNATION
TASK 12-24-38-680-001-A	Draining of the Potable Water System (with Electrical Power)
TASK 20-23-38-300-001-A	Repair of the Tubes Assembly of the Potable Water and the associated Air Supply System to be carried out in the Workshop
TASK 20-23-38-300-002-A	Repair of the Tubes of the Potable Water and the associated Air Supply System to be carried out in the Aircraft
TASK 20-23-38-300-048-A	Repair of the Tubes with H-Fittings to be carried out in the Aircraft
TASK 20-23-38-300-049-A	Temporary Repair of the Tube Assemblies with MS21922 Sleeves to be carried out in the Workshop
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 30-73-53-000-001-A	Removal of the Potable-Water De-icing Heater Elements
TASK 38-10-00-614-002-A	Depressurization of the Potable Water System
Connection of a (two) Tube(s) with Fittings
Usual Repair Procedures
Chipless Cutter
Tubes with a Flexible Coupling
Protection Hoses
Tee Half Box

3. Job Set-up
Subtask 20-23-38-861-053-A

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

Subtask 20-23-38-010-061-A

B. Get Access
(1) Remove/open the relevant access panels/doors to get access to the repair area.

Subtask 20-23-38-860-059-A

C. Aircraft Maintenance Configuration
(1) Make sure that the water system is the depressurized before maintenance action (Ref. AMM TASK 38-10-00-614-002).
(2) Make sure that the potable water system is emptied before maintenance action (Ref. AMM TASK 12-24-38-680-001).

Subtask 20-23-38-941-063-A

D. Safety Precautions
(1) Put a WARNING NOTICE(S) in position to tell personnel not to fill or pressurize the potable water system.

4. Procedure
Subtask 20-23-38-010-059-A

A. Removal of the Tube Assy Fitted with HARRISONS Sleeves and Unions

Connection of a (two) Tube(s) with Fittings

(1) Remove the potable-water de-icing heater elements:

For heater elements 4DW, 5DW, 6DW, 9DW (Ref. AMM TASK 30-73-53-000-001)
For heater elements 4DW, 9DW, 16DW (Ref. AMM TASK 30-73-53-000-001)
For heater elements 4DW, 311DW, 321DW, 322DW, 323DW, 331DW, 332DW (Ref. AMM TASK 30-73-53-000-001)
For heater elements 351DW, 352DW, 353DW, 361DW, 362DW, 363DW (Ref. AMM TASK 30-73-53-000-001)
For heater elements 4DW, 311DW, 321DW, 322DW, 323DW, 324DW, 331DW, 332DW (Ref. AMM TASK 30-73-53-000-001)
For heater elements 4DW, 16DW, 335DW (Ref. AMM TASK 30-73-53-000-001)

(2) Put a CONTAINER 1 L (1/4 USGAL) in position below the potable water line to collect the unwanted water.
(3) Carefully loosen the sleeve nut and remove the tube assembly.
(4) Put the PLUG-BLANKING in each disconnected line end.
(5) If necessary do the repair of the tube assembly (Ref. AMM TASK 20-23-38-300-049) (Ref. AMM TASK 20-23-38-300-001)

Subtask 20-23-38-010-062-A

B. Removal of a Tube Section fitted with PERMASWAGE Fittings

Usual Repair Procedures

(1) Remove the potable-water de-icing heater elements as necessary:

For heater elements 4DW, 5DW, 6DW, 9DW (Ref. AMM TASK 30-73-53-000-001).
For heater elements 4DW, 9DW, 16DW (Ref. AMM TASK 30-73-53-000-001).
For heater elements 4DW, 311DW, 321DW, 322DW, 323DW, 331DW, 332DW (Ref. AMM TASK 30-73-53-000-001).
For heater elements 351DW, 352DW, 353DW, 361DW, 362DW, 363DW (Ref. AMM TASK 30-73-53-000-001).
For heater elements 4DW, 311DW, 321DW, 322DW, 323DW, 324DW, 331DW, 332DW (Ref. AMM TASK 30-73-53-000-001).
For heater elements 4DW, 16DW, 335DW (Ref. AMM TASK 30-73-53-000-001).

(2) Put a CONTAINER 1 L (1/4 USGAL) in position below the potable water line to collect the unwanted water.
(3) Cut the tube end or section with a CUTTER - ROLLER TYPE, CHIPLESS

Chipless Cutter

(4) Remove the tube end or section.
(5) Put the PLUG-BLANKING in each disconnected line end.
(6) If necessary do the repair of the tube assembly (Ref. AMM TASK 20-23-38-300-048) (Ref. AMM TASK 20-23-38-300-002) and/or (Ref. AMM TASK 20-23-38-300-049)

Subtask 20-23-38-010-064-A

C. Removal of the Tube Assembly Fitted with Flexible Couplings (ABS0395)

Tubes with a Flexible Coupling

(1) If necessary, remove the insulation packs that are around the tubes (1) and (3).
(2) Remove the potable-water de-icing heater elements as necessary (Ref. AMM TASK 30-73-53-000-001).
(3) If necessary, remove the heater bridges from the tubes (1) and (3).
(4) Put a CONTAINER - CLEAN, APPLICABLE in position below the potable water line to collect the unwanted water.
(5) Remove the clamp (4).
(6) Move the sleeve (6) laterally on the tubes (1) and (3).

CAUTION: WHEN YOU DISCONNECT THE LINES, DO NOT BEND THEM TOO MUCH. IF YOU BEND THE LINES TOO MUCH, YOU CAN CAUSE DAMAGE TO THEM.

(7) Disconnect the tubes (1) and (3).
(8) Remove the sleeve (6).
(9) Remove and discard the O-rings (5).
(10) Put a PLUG - BLANKING on the disconnected line end(s).
(11) If necessary, do the repair of the disconnected tubes (1) and (3) (Ref. AMM TASK 20-23-38-300-001) (Ref. AMM TASK 20-23-38-300-002) (Ref. AMM TASK 20-23-38-300-048) or (Ref. AMM TASK 20-23-38-300-049).

Subtask 20-23-38-010-065-A

D. Removal of the Protection Hose Assembly

Protection Hoses

(1) Put a CONTAINER - CLEAN, APPLICABLE in position below the potable water line to collect the unwanted water.
(2) Loosen the clamp screws (2).
(3) Remove the clamps (5).
(4) Move the protection hoses (1) and (4) rearward along the tubes (6) and (8) until you can see the ends of the straight half shells (3).
(5) Remove the straight half shells (3) from the clamp (7).

Subtask 20-23-38-010-066-A

E. Removal of the Tee Half Boxes

Tee Half Box

(1) Put a CONTAINER - CLEAN, APPLICABLE in position below the potable water line to collect the unwanted water.
(2) If the tie wraps (1) are installed, remove and discard them.
(3) Loosen the screws (2) of the clamps (3).
(4) Remove the clamps (3).
(5) Remove the sealants with a SCRAPER - NON METALLIC.
(6) Remove the tee half boxes (4) from the tee (6) and discard them.
(7) If the seals (9) are installed, remove and discard them.
(8) Disconnect the pipes that are attached with the flexible couplings (ABS0395). For the removal of the flexible couplings, go to Paragraph 4.C.

[Rev.10 from 2021] 2026.04.01 04:49:58 UTC