SDR ASAA2019030228421

Service difficulty report · Filter · Boeing 737990ER

Difficulty date: March 2, 2019
Submitted: March 5, 2019
Operation: Air carrier
Aircraft: N474AS
Make and model: Boeing 737990ER
Aircraft serial: 40715
Aircraft time: 14,602 hours, 4,804 cycles
System (JASC): 2160 · Cabin Temperature Control System
Part: Filter
Condition: Dirty
Location: Ac Bay
Stage of operation: NR
How discovered: O
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

CONT CAB ZONE TEMP LIGHT ILLUMINATED ON MASTER RECALL. GROUNDED - YES. RELEASED PER MEL 21-21G FLIGHT DECK PRIMARY TEMP CONTROL INOP. VERIFIED FAULT, CLEANED ALL 3 TEMP SENSOR FILTERS. ACCOMP PACK ZONE TEMP CONT BITE TEST, CONTROLLER NR 1 NO FAULTS, CONTROLLER NR 2 SHOWS FLT DECK TRIM VALVE FAULT. CLEARED FAULT. ACCOMP PACK/ZONE TEMP CONT BITE TEST, TEST NOW PASSES NO FAULTS. REF AMM 21-61-20-860-005, AMM 21-61-06-100-801. A/C RELEASED FROM MEL 21-21G.