Operational Test of the APU Fire and Overheat Detection System

TASK 26-13-00-710-001-A
Operational Test of the APU Fire and Overheat Detection System

ZONE: 210

1. Reason for the Job
Refer to the MPD TASK: 261300-01
OPERATIONAL CHECK OF LOOP/SQUIB
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
210	CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 31-60-00-860-001-A	EIS Start Procedure
TASK 33-14-00-710-001-A	Operational Check of the Light Test System

3. Job Set-up
Subtask 26-13-00-860-050-A

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) Energize the ECAM system (Ref. AMM TASK 31-60-00-860-001).
(3) Do the operational test of the annunciator light test-system (Ref. AMM TASK 33-14-00-710-001).

Subtask 26-13-00-865-050-A

B. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	APU/FIRE AND OVHT/DET/LOOP B	2WG	L44
121VU	APU/FIRE AND OVHT/DET/LOOP A	1WG	L43
121VU	APU/FIRE/EXTIG/SQUIB/B	2WF	L39
121VU	APU/FIRE/EXTIG/SQUIB/A	1WF	L38
121VU	APU/FIRE/LP VALVE/NORM	4WF	M42
121VU	APU/FIRE/LP VALVE/STBY	3WF	M41

4. Procedure
Subtask 26-13-00-875-050-A ** ON A/C NOT FOR ALL

A. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	APU/AUTO/EXTIG/GND/TEST	30WF	L40

Subtask 26-13-00-710-050-A ** ON A/C NOT FOR ALL

B. Operational Test of the APU Fire and Overheat Detection System

Make sure that circuit breaker APU AUTO EXTIG GND TEST 30WF (L40) on panel 121VU is open.

NOTE: You can open circuit breaker APU AUTO EXTIG GND TEST 30WF (L40) to prevent an unwanted automatic fire-extinguisher discharge during the test.

ACTION	RESULT
1.On panel 25VU: Push the APU MASTER SW to ON.	On panel 25VU: The blue ON light in the APU MASTER SW comes on.
WARNING: DO NOT PUSH THE APU FIRE/TEST PUSHBUTTON SWITCH FOR MORE THAN 3 SECONDS. IF YOU PUSH IT FOR MORE THAN 3 SECONDS, THERE IS A RISK THAT IT WILL CAUSE THE DISCHARGE OF THE APU FIRE-EXTINGUISHER BOTTLE. 2.On ENG/APU FIRE panel (1WD), on 20VU: Push and hold the APU FIRE/TEST pushbutton switch for not more than 3 seconds.	On ENG/APU FIRE panel (1WD), on 20VU: On the APU FIRE/TEST pushbutton switch, the APU FIRE light comes on. The first and the third column of the APU FIRE light come on. NOTE: When the aircraft supply is from the batteries, the APU fire pushbutton test shows only the status of the fire loop A but not the status of the fire loop B. NOTE: If the aircraft is fully energized, all the columns of the APU FIRE light come on. On the AGENT pushbutton switch, the SQUIB and DISCH lights come on. On glareshield panels 130VU and 131VU: The MASTER WARN lights flash. You hear a continuous repetitive chime. On the ECAM upper display unit: The warnings that follow come on: APU FIRE APU FIRE P/B....PUSH MASTER SW....OFF.
Release the APU FIRE/TEST pushbutton switch.	All the warnings go off.
3.On panel 25VU: Release the APU MASTER SW to OFF.	On panel 25VU: The blue ON light in the APU MASTER SW goes off.

Subtask 26-13-00-710-050-B ** ON A/C NOT FOR ALL

B. Operational Test of the APU Fire and Overheat Detection System

ACTION	RESULT
1.On panel 25VU: Push the APU MASTER SW to ON.	On panel 25VU: The blue ON light in the APU MASTER SW comes on.
WARNING: DO NOT PUSH THE APU FIRE/TEST PUSHBUTTON SWITCH FOR MORE THAN 3 SECONDS. IF YOU PUSH IT FOR MORE THAN 3 SECONDS, THERE IS A RISK THAT IT WILL CAUSE THE DISCHARGE OF THE APU FIRE-EXTINGUISHER BOTTLE. 2.On ENG/APU FIRE panel (1WD), on 20VU: Push and hold the APU FIRE/TEST pushbutton switch for not more than 3 seconds.	On ENG/APU FIRE panel (1WD), on 20VU: On the APU FIRE/TEST pushbutton switch, the APU FIRE light comes on. The first and the third column of the APU FIRE light come on. NOTE: When the aircraft supply is from the batteries, the APU fire pushbutton test shows only the status of the fire loop A but not the status of the fire loop B. NOTE: If the aircraft is fully energized, all the columns of the APU FIRE light come on. On the AGENT pushbutton switch, the SQUIB and DISCH lights come on. On glareshield panels 130VU and 131VU: The MASTER WARN lights flash. You hear a continuous repetitive chime. On the ECAM upper display unit: The warnings that follow come on: APU FIRE APU FIRE P/B....PUSH MASTER SW....OFF.
Release the APU FIRE/TEST pushbutton switch.	All the warnings go off.
3.On panel 25VU: Release the APU MASTER SW to OFF.	On panel 25VU: The blue ON light in the APU MASTER SW goes off.

Subtask 26-13-00-875-051-A ** ON A/C NOT FOR ALL

C. 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/AUTO/EXTIG/GND/TEST	30WF	L40

5. Close-up
Subtask 26-13-00-860-051-A

A. Put the aircraft back to its initial configuration.
(1) On the ECAM control panel set the Control/Brightness knobs to OFF.
(2) De-energize the annunciator light test and dimming system (Ref. AMM TASK 33-14-00-710-001).
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.03.31 23:43:37 UTC