SDR ASAA2017110822482

Service difficulty report · Filter · Boeing 737990ER

Difficulty date: November 8, 2017
Submitted: November 9, 2017
Operation: Air carrier
Aircraft: N472AS
Make and model: Boeing 737990ER
Aircraft serial: 60580
Aircraft time: 10,340 hours, 3,385 cycles
System (JASC): 2160 · Cabin Temperature Control System
Part: Filter
Condition: Dirty
Location: Temp Sensor
Stage of operation: NR
How discovered: 9
Nature of condition: O
Precautionary procedure: O

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

What was found

CABIN TEMPERATURE ON FLIGHT DECK BECAME UNCONTROLLABLY HOT. WHEN SUPPLY DUCT TEMPERATURE FOR CONTROL CABIN REACHED 45 DEGREES C WE PERFORMED QRH CHECKLIST FOR CABIN TEMPERATURE HOT 800/900. REGAINED TEMPERATURE CONTROL WHEN TRIM AIR SWITCH AND LEFT PACK SWITCH TURNED OFF. ACFT GROUNDED. IAW FIM 21-61 TASK 861 PERFORMED PACK BITE PROCEDURE, NO FAULTS FOUND. CLEANED CONTROL CABIN TEMP SENSOR FILTER IAW AMM 21-61-06. OPS CHECKED SATISFACTORY. AIRCRAFT OK FOR SERVICE.