SDR ASAA2023010341405

Service difficulty report · Modulating Valve · Boeing 737890

Difficulty date: January 3, 2023
Submitted: January 5, 2023
Operation: Air carrier
Aircraft: N518AS
Make and model: Boeing 737890
Aircraft serial: 35693
Aircraft time: 50,600 hours, 14,835 cycles
System (JASC): 2160 · Cabin Temperature Control System
Part: Modulating Valve
Part number: UNKNOWN
Condition: Faulted
Location: Unknown
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

DURING AFTER START RECALL, MASTER CAUTION "AIR COND" CONT CABIN "ZONE TEMP" ILLUMINATED, RESET WITH MASTER CAUTION, RAN QRH-SUCCESSFUL. GROUNDED - YES. #2 PACK TEMP BITE SHOWS FLT DECK TRIM VALVE FAULT, MSG CLEARED, RAN PACKS & RE-VERIFY BITE, TEST PASS REF B737-800 FIM 21-60 TASK 801. NO HISTORY PAST 30 DAYS.