Removal of the Lower Anti-Ice Valve

TASK 30-21-51-000-803-A
Removal of the Lower Anti-Ice Valve

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

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.

FIN: 4011DN ** 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	1	ACCESS PLATFORM 1M(3 FT)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 30-21-12-000-801-A	Removal of the Nacelle Anti-Ice Sense-Tubes
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
Lower Anti-Ice Valve

3. Job Set-up
Subtask 30-21-51-941-061-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 30-21-51-865-078-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 30-21-51-010-073-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR

Subtask 30-21-51-040-053-A ** ON A/C NOT FOR ALL

D. 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) Do the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 30-21-51-010-074-A ** ON A/C NOT FOR ALL

E. Get Access
(1) Open the right thrust reverser cowl-door (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
462AR
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

4. Procedure
Subtask 30-21-51-020-058-A ** ON A/C NOT FOR ALL

A. Removal of the Lower Anti-Ice Valve
(1) Find the lower anti-ice valve (1) at approximately 6 o'clock near the mid turbine frame case.
(2) Disconnect the aft sense tube from the lower anti-ice valve (1) (Ref. AMM TASK 30-21-12-000-801).
(3) Remove the coupling (2) and seal (3) between the bottom end of the lower anti-ice valve (1) and the mid anti-ice duct.
(4) Keep the seal (3) for installation.
(5) Hold the anti-ice valve (1) and remove the coupling (4) and seal (5) between the top end of the lower anti-ice valve (1) and the short anti-ice duct.
(6) Remove the lower anti-ice valve (1).
(7) Keep the seal (5) for installation.
(8) Put the COVER - PROTECTION on the duct openings, on the short anti-ice duct and on the mid anti-ice duct.
(9) Put the CAP - PROTECTION on the aft-sense tube connection.
(10) Put the COVER - PROTECTION on the openings of the lower anti-ice valve (1).

[Rev.10 from 2021] 2026.04.01 00:30:26 UTC