# SDR ASAA2015101513511

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 15, 2015
- Submitted: October 20, 2015
- Operation: Air carrier
- Aircraft: [N486AS](https://openairdocs.org/aircraft/N486AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44107
- Aircraft time: 187 hours, 64 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Controller
- Condition: Malfunctioned
- Location: Cabin Temp
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2015101513511

## Discrepancy

TEMP CONTROL IN ALL 3 ZONES "HYPER-SENSITIVE", LARGER THAN USUAL SUPPLY DUCT TEMP CHANGES WITH SMALL ADJUSTMENTS.  CONDITION MOST PRONOUNCED AFTER ENGINE START & TAKE OFF, THEN IMPROVED ENROUTE.  WHEN TEMP SELECTORS OFF: ON GROUND SUPPLY DUST TEMP IN ALL 3 ZONES INDICATES 38-40C IN FLIGHT, CONTROL CAB INDICATES 38-40C, FWD & AFT CAB INDICATOR NORMAL 20-22C.  ACFT GROUNDED.  REF AMM 21-62, TASK 801 BITE CK SYS.  NO FAULTS FOUND.  CYCLED PACKS HOT/COLD.  OPS NORMAL.  NO 30DAY HISTORY.  OK FOR SERVICE.

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