Removal of the Potable Water De-icing Sensor

TASK 30-73-18-000-001-A
Removal of the Potable Water De-icing Sensor

ZONE: 121
FIN: 29DW ** ON A/C NOT FOR ALL

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

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 2M (6 FT)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
121	AVIONICS COMPARTMENT
131GW, 825

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 52-30-00-860-001-A	Open the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
Removal/Installation of Bleed Duct for Access
Sensor

3. Job Set-up

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.

Subtask 30-73-18-861-050-A ** ON A/C NOT FOR ALL

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

Subtask 30-73-18-865-050-A ** ON A/C NOT FOR ALL

B. 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/BLOWER/FAN	1HQ	AD10
123VU	AVNCS VENT/EXTC/FAN	2HQ	AE02
2000VU	POT/WASTE WIP-HEATER-LINE	21DW	A03
2000VU	POT/WASTE WIP-HEATER-CTL	2DW	A01

Subtask 30-73-18-010-050-B ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 2M (6 FT) at the FWD cargo-compartment door 825.
(2) Open the FWD cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-001).
(3) Set the CARGO COMPT LIGHT switch 6LU to ON.
(4) In the FWD cargo compartment, remove the sidewall panel 131GW.

Subtask 30-73-18-010-051-A ** ON A/C NOT FOR ALL

D. Removal for Access to the Sensor

Removal/Installation of Bleed Duct for Access ** ON A/C NOT FOR ALL

(1) Remove the clamp (10).
(2) Remove the clamps (7).
(3) Hold the duct (9) and remove the clamp (8).
(4) Remove the duct (9) and discard the O-ring (11).

4. Procedure
Subtask 30-73-18-020-050-B ** ON A/C NOT FOR ALL

A. Removal of the Potable Water De-icing Sensor
(1) Cut the tie-down straps (1) that attach the glass wool mat (6) around the sensor.
(2) Remove the glass wool mat (6) from around the clamp sensor assembly (2) and the clamp (3).
(3) Disconnect the two wires of the clamp sensor assembly (2) from the terminal strip.
(4) On the potable water pipe, loosen and remove the screws (4) and (5) from the clamp sensor assembly (2) and the clamp (3).
(5) Remove the clamp (3).
(6) Remove the clamp sensor assembly (2).

[Rev.10 from 2021] 2026.04.01 00:32:38 UTC