Installation of the Oxygen Filling Indicator

TASK 35-13-21-400-001-A
Installation of the Oxygen Filling Indicator

WARNING: KEEP ALL HYDROCARBONS (FUELS, LUBRICANTS, ETC.) AWAY FROM ALL SOURCE OF OXYGEN. OXYGEN BECOMES EXPLOSIVE WHEN IT TOUCHES HYDROCARBONS.

WARNING: CLEAN THE TOOLS AND MAKE SURE YOUR HANDS ARE CLEAN TO PREVENT CONTAMINATION OF THE OXYGEN SYSTEM.

ZONE: 123
ZONE: 125
FIN: 5HT ** ON A/C NOT FOR ALL
FIN: 5HT1 ** ON A/C NOT FOR ALL
FIN: 5HT2 ** 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	CAP - BLANKING

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
123	NOSE GEAR WELL
125	LATERAL AVIONIC COMPARTMENT
812

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 35-00-00-860-001-A	Special Precautions When Working on a Gaseous Oxygen System
Oxygen Filling Indicator ** ON A/C NOT FOR ALL
Oxygen Filling Indicator ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 35-13-21-860-051-A

A. Aircraft Maintenance Configuration
(1) Obey the special precautions when you do work on a gaseous oxygen system (Ref. AMM TASK 35-00-00-860-001).
(2) Make sure that the ACCESS PLATFORM 2M (6 FT) is in position at access door 812.
(3) Make sure that access door 812 is open.
(4) Make sure that the ground service network is energized (Ref. AMM TASK 24-42-00-861-001).

Subtask 35-13-21-865-051-A

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	OXYGEN/CREW/OXY/SPLY	1HT	HA01

4. Procedure
Subtask 35-13-21-420-050-A ** ON A/C NOT FOR ALL

A. Installation of the Oxygen Filling Indicator
(1) Put the indicator (1) in the clamp (3).
(2) Tighten the adjusting screw (2).
(3) Remove the CAP - BLANKING from the electrical connector (4).
(4) Connect the electrical connector (4) to the indicator (1).

Subtask 35-13-21-420-050-B ** ON A/C NOT FOR ALL

A. Installation of the Oxygen Filling Indicator
(1) Remove the oxygen filling indicator (4) from the BAG - VINYL, SEALED.
(2) Put the oxygen filling indicator (4) in position on the support plate (5).
(3) Put the clamp (2) in the oxygen filling indicator (4).
(4) Tighten the adjusting screws (3).
(5) Remove the CAP - BLANKING from the electrical connector (1).

CAUTION: MAKE SURE THAT THE ELECTRICAL CONNECTORS ARE CLEAN BEFORE YOU DISCONNECT OR CONNECT THEM. CONTAMINATION ON THE ELECTRICAL CONNECTORS CAN CAUSE DAMAGE TO EQUIPMENT.

(6) Connect the electrical connector (1) to the oxygen filling indicator (4).

Subtask 35-13-21-865-052-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	OXYGEN/CREW/OXY/SPLY	1HT	HA01

Subtask 35-13-21-820-050-A ** ON A/C NOT FOR ALL

C. Test of the Oxygen Filling Indicator
(1) Make sure that the pressures read on the oxygen filling indicator (1) and on the oxygen-cylinder pressure gage are the same.

Subtask 35-13-21-820-050-B ** ON A/C NOT FOR ALL

C. Test of the Oxygen Filling Indicator
(1) FOR [5HT1] (IND OXY FILLING)
(a) Make sure that the pressures read on the oxygen filling indicator (4) and on the pressure gage of the crew oxygen-storage cylinder 5750HM1 are the same.
(2) FOR [5HT2] (IND OXY FILLING)
(a) Make sure that the pressures read on the oxygen filling indicator (4) and on the pressure gage of the crew oxygen-storage cylinder 5750HM2 are the same.

5. Close-up
Subtask 35-13-21-860-052-A

A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) De-energize the ground service network (Ref. AMM TASK 24-42-00-862-001).
(3) In the cockpit, on the OXYGEN section of the overhead control and indicating panel 21VU:

Remove the WARNING NOTICE(S).

Subtask 35-13-21-410-050-A

B. Close Access
(1) Close access door 812.
(2) Remove the access platform(s).

[Rev.10 from 2021] 2026.04.01 01:04:37 UTC