Installation of the Thermocouples (131-9(A))

TASK 49-72-15-400-003-A
Installation of the Thermocouples (131-9(A))

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

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

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE
No specific	Torque wrench: range to between 44 and 36 lbf.in (0.50 and 0.41 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.03PBB1)	Lubricant-Anti Seize High Temp. -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315AL, 316AR

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
2	GASKET	AIPC 49-72-09-01-030

E. 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 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-00-00-710-009-A	Self-Test of the ECB
TASK 52-41-00-010-001-A	Open the APU Doors for Access
TASK 52-41-00-410-001-A	Close the APU Doors after Access
Thermocouples

3. Job Set-up
Subtask 49-72-15-860-062-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).
(2) On the panel 25VU make sure that the APU MASTER SW p/bsw is OFF.
(3) Make sure that there is a warning notice in the cockpit to tell persons not to start the APU.
(4) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-00-00-864-001).

Subtask 49-72-15-865-058-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41

Subtask 49-72-15-010-056-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE in position below the APU access doors 315AL and 316AR.
(2) Open the APU access doors 315AL and 316AR (Ref. AMM TASK 52-41-00-010-001).
(3) Set the LIGHT SW 11LJ to the ON position.

4. Procedure
Subtask 49-72-15-420-052-A ** ON A/C NOT FOR ALL

A. Installation of the Thermocouples
(1) Put the new AIPC 49-72-09-01-030 GASKET (2) in position on the thermocouple (3).
(2) Remove the blanking plug from the thermocouple flange.
(3) Put the thermocouple (3) into the APU.
(4) Turn the thermocouple (3) to engage mounting plate on studs.
(5) Apply a thin layer of Lubricant-Anti Seize High Temp. - (Material No.03PBB1) to the threads of the studs.
(6) Install the nuts (1) to secure the thermocouple in the APU.
(7) TORQUE the nuts (1) to between 44 and 36 lbf.in (0.50 and 0.41 m.daN )

.
(8) Install the electrical connections (4) with the nuts (5) and (6).
(9) Tighten the nuts (5) and (6).

Subtask 49-72-15-865-059-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
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41

Subtask 49-72-15-710-053-A ** ON A/C NOT FOR ALL

C. Do the self test of the ECB (Ref. AMM TASK 49-00-00-710-009).

5. Close-up
Subtask 49-72-15-410-053-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 APU access doors 315AL 316AR and (Ref. AMM TASK 52-41-00-410-001).
(3) Remove the access platform(s).

Subtask 49-72-15-860-063-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Put the related hydraulic system in the pressurized configuration (Ref. AMM TASK 29-00-00-864-001).
(2) De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 01:32:11 UTC