SDR ASAA2018020123362

Service difficulty report · Filter · Boeing 737990ER

Difficulty date: February 1, 2018
Submitted: February 2, 2018
Operation: Air carrier
Aircraft: N481AS
Make and model: Boeing 737990ER
Aircraft serial: 44106
Aircraft time: 9,958 hours, 3,354 cycles
System (JASC): 2160 · Cabin Temperature Control System
Part: Filter
Condition: Dirty
Location: Cabin Air
Stage of operation: DE
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 DESCENT, THE AFT ZONE TEMP LIGHT ILLUMINATED. RAN QRH, LIGHT REMAINED ILLUMINATED. ACFT GROUNDED. FWD CARGO HEAT DUCT OPENED, PACK AIRFLOW SHUTOFF VALVE ACTIVATED AND OPENED IAW AMM 21-00-00. ACCOMPLISHED CABIN TEMP CONTROL AND INDICATION IAW AMM 21-61-00-700-807-002. COULD NOT DUPLICATE. FOUND ALL THREE TEMP SENSORS, FLT DECK, FWD, AFT, FILTERS CONTAMINATED. IAW AMM 21-61-14-100-802 ACCOMPLISHED A TEMP SENSOR HOUSING ASSY CLEANING. OPS TESTED NORMAL.