SDR ASAA2021101336284

Service difficulty report · Modulating Valve · Boeing 737990ER

Difficulty date: October 13, 2021
Submitted: October 18, 2021
Operation: Air carrier
Aircraft: N402AS
Make and model: Boeing 737990ER
Aircraft serial: 41189
Aircraft time: 33,160 hours, 10,677 cycles
System (JASC): 2160 · Cabin Temperature Control System
Part: Modulating Valve
Part number: 3989083
Part serial: 7670
Condition: Inoperative
Location: Right Ecs Bay
Part time: 63,128 hours, 19,160 cycles
Stage of operation: NR
How discovered: V
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

FWD CABIN ZONE TEMP LIGHT ILLUMINATES ON MASTER CAUTION RECALL EXTINGUISHES ON MASTER CAUTION RESET. GROUNDED - YES. #2 ZONE TEMP CONT FAULTED THIS PACK TCV ON BIT, PREV FLT, & VERIFY. REF CORRECTIVE ACTION ON LOG 60252989, AFTER PART REPLACED & MSG RESET, RAN PACKS & RECONFIRM BITE, SYSTEM OPS NORMAL.