Service difficulty report · Modulating Valve · Boeing 737990ER

Difficulty date
September 5, 2023
Submitted
September 7, 2023
Operation
Air carrier
Aircraft
N431AS
Make and model
Boeing 737990ER
Aircraft serial
43255
Aircraft time
36,445 hours, 11,516 cycles
Part
Modulating Valve
Part number
3989085
Part serial
11899C
Condition
Faulty
Location
Rh Ecs Bay
Part time
48,303 hours, 15,224 cycles
Stage of operation
NR
How discovered
V
Nature of condition
J
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

ON MASTER RECALL R PACK LIGHT ILLUMINATES. OFF WHEN RESET WITH MASTER CAUTION. GROUNDED - YES. REMOVED AND REPLACED RH TEMPERATURE CONTROL VALVE IAW AMM 21-51-10-000-801 AND AMM 21-51-10-400-801, ETOPS GROUND FUNCTIONAL CHECK GOOD IAW AMM 21-61-00-700-806-002. CLEARS MEL 21-32B, SEAMC ASHRAF NOTIFIED, NO AIRCRAFT CONFIGURATION CHANGE.