# SDR ASAA2017120522795

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 5, 2017
- Submitted: December 7, 2017
- Operation: Air carrier
- Aircraft: [N486AS](https://openairdocs.org/aircraft/N486AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44107
- Aircraft time: 8,939 hours, 2,994 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Filter
- Part number: 412A160541
- Condition: Faulted
- Location: Cabin Air
- Stage of operation: NR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2017120522795

## Discrepancy

FWD CAB TEMP CONTROL VERY IRREGULAR AND ERRATIC. WHEN PLACED AT THE 8-9 OCLOCK POSITION TEMP GOES FROM VERY HOT TO VERY COLD. IN ALL PHASES OF FLIGHT. TRIM AIR ON. ALL OTHER TEMP SELECTORS OPS NORMAL. GROUNDED - YES. FOUND FWD PASSENGER CAB TEMP CONTROL SENSOR GRILL TAPED WITH BLUE MASKING TAPE. VERIFIED NO AIRFLOW TO TEMP SENSOR. REMOVED TAPE FROM GRILL. REPLACED TEMP SENSOR FILTER PRECAUTIONARY REF B737-900 AMM 21-62-06. GROUND VERIFICATION TEST PASSED REF AMM 21-60-00.

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