Installation of the Lower Anti-Ice Valve

TASK 30-21-51-400-803-A
Installation 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	1	HAMMER - FIBER
No specific	Torque wrench: range to between 70 and 55 lbf.in (0.79 and 0.62 m.daN )

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 30-21-00-710-002-A	Operational Check of the Engine-Air-Intake Ice-Protection System (with the Engines in operation)
TASK 30-21-12-400-801-A	Installation of the Nacelle Anti-Ice Sense-Tubes
TASK 71-00-00-790-802-A	Test No. 1 - Pneumatic Leak Test
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 71-13-00-410-802-A	Closing of the Fan Cowl Doors
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
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors
Lower Anti-Ice Valve

3. Job Set-up
Subtask 30-21-51-941-063-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Make sure that you did the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).

Subtask 30-21-51-865-081-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
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 30-21-51-010-077-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Make sure that the fan cowl doors are open (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 30-21-51-040-055-A ** ON A/C NOT FOR ALL

D. Deactivation of the Thrust Reverser System 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) Make sure that you did the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 30-21-51-010-078-A ** ON A/C NOT FOR ALL

E. Get Access
(1) Make sure that the right thrust reverser cowl-door is open (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) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.

4. Procedure
Subtask 30-21-51-420-058-A ** ON A/C NOT FOR ALL

A. Installation of the Lower Anti-Ice Valve

CAUTION: MAKE SURE THE FLOW ARROW ON THE LOWER ANTI-ICE VALVE POINTS AWAY FROM THE SHORT ANTI-ICE DUCT. IF THE FLOW ARROW POINTS IN THE INCORRECT DIRECTION, THE LOWER ANTI-ICE VALVE WILL NOT OPERATE CORRECTLY AND CAN CAUSE DAMAGE TO EQUIPMENT.

(1) Remove the COVER - PROTECTION from the duct openings and the sense tube connection.
(2) Install the coupling (4) and seal (5) between the top end of the lower anti-ice valve (1) and the short anti-ice duct.
(3) Make sure that the tabs on the short anti-ice duct fit into the slots on the lower anti-ice valve (1).
(4) Tighten the coupling (4) sufficiently to hold the lower anti-ice valve (1) to the short anti-ice duct.

NOTE: Do not torque the coupling (4) at this time.

(5) Install the coupling (2) and seal (3) between the bottom end of the lower anti-ice valve (1) and the mid anti-ice duct.
(6) Tighten the coupling (2) sufficiently to hold the lower anti-ice valve (1) to the mid anti-ice duct.

NOTE: Do not torque the coupling (2) at this time.

(7) Position the couplings (2) and (4) so that the nuts are facing down.
(8) Make sure that the nut on the couplings (2) is on the outboard side of the lower anti-ice valve (1).
(9) Make sure that the nut on the coupling (4) is on the inboard side of the valve (1).
(10) Torque the couplings (2) and (4) as follows:
(a) TORQUE the nuts on the couplings (2) and (4) to between 70 and 55 lbf.in (0.79 and 0.62 m.daN )

.
(b) Tap around the outer surface of the couplings (2) and (4) with a HAMMER - FIBER.
(c) TORQUE the nuts on the couplings (2) and (4) again to between 70 and 55 lbf.in (0.79 and 0.62 m.daN )

.
(d) Tap around the outer surface of the couplings (2) and (4) with a HAMMER - FIBER.
(e) TORQUE the nuts on the couplings (2) and (4) a third time to between 70 and 55 lbf.in (0.79 and 0.62 m.daN )

.
(f) Tap around the outer surface of the couplings (2) and (4) with a HAMMER - FIBER.
(g) TORQUE the nuts on the couplings (2) and (4) to between 70 and 55 lbf.in (0.79 and 0.62 m.daN )

.
(h) Make sure that you can see two full threads past the nuts on the couplings (2) and (4).
(11) Connect the aft sense tube to the lower anti-ice valve (1) (Ref. AMM TASK 30-21-12-400-801).

Subtask 30-21-51-210-061-A ** ON A/C NOT FOR ALL

B. Visual Inspection and Tests
(1) Do the pneumatic leak test (Ref. AMM TASK 71-00-00-790-802) and when you operate the engine at the minimum IDLE power, do the operational test of the engine air-intake ice protection (Ref. AMM TASK 30-21-00-710-002).

5. Close-up
Subtask 30-21-51-410-073-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) Remove the access platform(s).
(3) Close the right thrust reverser cowl-door (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
462AR

Subtask 30-21-51-440-055-A ** ON A/C NOT FOR ALL

B. Do the reactivation of the thrust reverser system after maintenance (Ref. AMM TASK 78-30-00-440-805).

Subtask 30-21-51-410-074-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR
(2) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 00:30:27 UTC