Deactivation of the NAI Lower Valve

TASK 30-21-00-040-804-A-01
Deactivation of the NAI Lower Valve

WARNING: WEAR APPLICABLE PERSONAL PROTECTIVE EQUIPMENT (PPE) WHEN YOU DO THIS TASK. BEFORE YOU USE PPE, READ, UNDERSTAND AND OBEY ALL INSTRUCTIONS FOR ITS USE. THESE INSTRUCTIONS INCLUDE INSTRUCTIONS FROM THE MANUFACTURER, YOUR EMPLOYER AND GOVERNMENT REGULATIONS. YOU CAN GET INJURED IF YOU DO NOT USE PPE. GET INSTRUCTIONS FROM YOUR EMPLOYER ON WHICH PPE IS NECESSARY.

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AND THE ADJACENT COMPONENTS AFTER ENGINE SHUTDOWN. THE ENGINE, THE ENGINE OIL AND THE ADJACENT COMPONENTS CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

CAUTION: MAKE SURE THAT THERE IS ALWAYS AN ANTI-ICE VALVE (UPPER OR LOWER) ACTIVATED DURING FLIGHT. IF THE TWO VALVES ARE DEACTIVATED, DAMAGE TO COMPONENTS CAN OCCUR.

ZONE: 210
ZONE: 400
FIN: 4011DN ** ON A/C NOT FOR ALL

1. Reason for the Job
MMEL 30-21-01B
ENGINE ANTI-ICE VALVE
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	DRIVE 1/4 IN - SQUARE
No specific	1	EXTENSION LENGHT 6 IN (152,4 MM)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	SCREWDRIVER
No specific	AR	WARNING NOTICE(S)
No specific	1	WRENCH 1/4 IN - RATCHET

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
210	CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD
400	POWER PLANT, NACELLES AND PYLONS

C. Referenced Information

REFERENCE	DESIGNATION
TASK 30-21-00-040-804-A	Deactivation of the NAI Lower Valve with the Thrust Reverser Door Open
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A	Reactivation of the Thrust Reverser System after Ground Maintenance
Lower Anti-Ice Valve

3. Job Set-up
Subtask 30-21-00-941-068-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).

Subtask 30-21-00-865-114-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
FOR FIN: 4020KM1 (POWER PLANTDEMOUNTABLE, ENG 1)
122VU	ANTI ICE/ENG/1	1DN1	X10
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
122VU	ANTI ICE/ENG/2	1DN2	W10

Subtask 30-21-00-040-090-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser for Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Open the oil tank access-door on the left fan cowl-door and do the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-805).

4. Procedure
Subtask 30-21-00-040-092-A ** ON A/C NOT FOR ALL

A. Deactivation of the NAI Lower Valve
(1) Remove the NAI lower valve access plug from the thrust reverser Inner Fixed Structure (IFS):

NOTE: You can get access to the anti-ice-valve manual-override interface, if you open the right fan-cowl door and right thrust-reverser door as an alternative (Ref. AMM TASK 30-21-00-040-804).

(a) Put the applicable SCREWDRIVER in the access plug.

CAUTION: DO NOT USE TOO MUCH FORCE WHEN YOU PUSH AND TURN THE ACCESS PLUG WITH THE SCREWDRIVER. IF YOU DO NOT OBEY THIS PRECAUTION, YOU CAN CAUSE DAMAGE TO THE ACCESS PLUG.

(b) Carefully, push the access plug a small distance and turn the access plug approximately 90 degrees counterclockwise to release the access plug from the port sleeve.
(c) Make sure that "OPEN" mark on the access plug aligns with "CAP" mark on the IFS. See detail B of the figure.
(d) Remove the access plug from the port sleeve.

NOTE: The access plug is attached to the IFS with a lanyard.

(2) Lock the NAI lower valve in the open position:
(a) Put a DRIVE 1/4 IN - SQUARE with an EXTENSION LENGHT 6 IN (152,4 MM) in the square hole of the manual override interface.

CAUTION: WHEN YOU TURN THE MANUAL OVERRIDE INTERFACE, DO NOT APPLY A FORCE OF MORE THAN 115 lbf.in (1.3 m.daN). IF YOU DO NOT OBEY THIS INSTRUCTION, YOU CAN CAUSE INTERNAL DAMAGE TO THE NAI VALVE.

(b) Push in the DRIVE 1/4 IN - SQUARE with the EXTENSION LENGHT 6 IN (152,4 MM) and turn the interface 270 degrees counterclockwise with a WRENCH 1/4 IN - RATCHET.
(c) Release the pressure on the interface.
(d) Make sure that the manual override interface locks in position.
(e) Make sure that the indicator on the valve manual-override interface aligns with "LOCKED OPEN" indication on the thrust reverser IFS.
(3) Install the NAI lower valve access plug back on the thrust reverser IFS:
(a) Put the access plug in position on the port sleeve.
(b) Make sure that the tabs on the access plug correctly engage the splines in the port sleeve.

CAUTION: DO NOT USE TOO MUCH FORCE WHEN YOU PUSH AND TURN THE ACCESS PLUG WITH THE SCREWDRIVER. IF YOU DO NOT OBEY THIS PRECAUTION, YOU CAN CAUSE DAMAGE TO THE ACCESS PLUG.

(c) Carefully, push the access plug a small distance with an applicable SCREWDRIVER and turn the access plug approximately 90 degrees clockwise to attach the access plug.
(d) Make sure that "CLOSE" mark on the access plug aligns with "CAP" mark on the IFS. See detail C of the figure.
(e) Make sure that you fully engage and correctly attach the access plug.

5. Close-up
Subtask 30-21-00-440-089-A ** ON A/C NOT FOR ALL

A. Do the reactivation of the thrust reverser system after maintenance and close the oil tank access-door on the left fan cowl-door (Ref. AMM TASK 78-30-00-440-805).

Subtask 30-21-00-865-115-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
FOR FIN: 4020KM1 (POWER PLANTDEMOUNTABLE, ENG 1)
122VU	ANTI ICE/ENG/1	1DN1	X10
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
122VU	ANTI ICE/ENG/2	1DN2	W10

Subtask 30-21-00-942-055-A ** ON A/C NOT FOR ALL

C. Put the aircraft back to its initial configuration.
(1) Remove the WARNING NOTICE(S).
(2) Put a WARNING NOTICE(S) in position in the cockpit to tell persons that the NAI lower valve is deactivated in the open position.
(3) Make an entry in the logbook.

[Rev.10 from 2021] 2026.04.01 00:28:52 UTC