Service difficulty report · Control Valve · Boeing 737990ER

Difficulty date
August 25, 2018
Submitted
August 27, 2018
Operation
Air carrier
Aircraft
N478AS
Make and model
Boeing 737990ER
Aircraft serial
44105
Aircraft time
12,565 hours, 4,246 cycles
Part
Control Valve
Part number
3989085
Part serial
1704
Condition
Failed
Location
Rt A/C Pack
Part time
77,427 hours, 36,759 cycles
Stage of operation
NR
How discovered
O
Nature of condition
J
Precautionary procedure
O

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

What was found

DURING RECALL, THE PACK LIGHT ILLUMINATED, RESET ON RECALL. ACFT GROUNDED. TROUBLESHOT AND FOUND THE RT TEMP CONTROL VALVE AT FAULT. REMOVED AND REPLACED THE RT PACK TEMP CONTROL VALVE IAW AMM 21-51-10, OPS & LEAK CHECKED GOOD.