No Water Available from the Potable Water System

TASK 38-12-00-810-816-A
No Water Available from the Potable Water System

1. Possible Causes

WTR SYSTEM DEPR

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 12-15-38-613-001	Fill the Potable Water Tank System (Aircraft Electrical Power Available)
AMM 38-10-00-614-001	Pressurization of the Potable Water System from a Ground Air Supply

3. Fault Confirmation
Subtask 38-12-00-710-082-A

A. Aircraft configuration
(1) Make sure that there is water in the potable water system, if necessary do the servicing AMM 12-15-38-613-001.
(2) Make sure that the potable water system is pressurized AMM 38-10-00-614-001.

4. Fault Isolation
Subtask 38-12-00-810-066-A ** ON A/C NOT FOR ALL

A. If the Flight Attendant Panel (FAP) gives the message NO WATER PRESSURE:
(1) Make sure that the light in the membrane switch on the FAP 120RH WTR SYSTEM DEPR is not on.
(a) The light in the membrane switch WTR SYSTEM DEPR must be off.
(b) If the light in the membrane switch WTR SYSTEM DEPR is on, push the membrane switch again.

Subtask 38-12-00-810-066-B ** ON A/C NOT FOR ALL

A. If the Flight Attendant Panel (FAP) gives the message NO WATER PRESSURE:
(1) Make sure that the light in the pushbutton key WTR SYSTEM DEPR on the FAP 120RH is not on.
(a) The light in the pushbutton key WTR SYSTEM DEPR must be off.
(b) If the light in the pushbutton key WTR SYSTEM DEPR is on, push the pushbutton key again.
(c) On the FAP WWP-List box, the message VACUUM SYSTEM DISABLE - WATER DEPRESS ACTIVE must not be shown.
(d) On the aircraft symbol, the message NO WATER PRESSURE must not be shown.

5. Close-up
Subtask 38-12-00-710-083-A

A. Aircraft Maintenance Configuration
(1) Make sure that the potable water system is pressurized AMM 38-10-00-614-001.
(2) Operate the water faucets and the toilet flush switches and make sure that they operate correctly.

[Rev.8 from Aug 2018] 2026.04.04 04:34:12 UTC