# SDR ASAA2014030507090

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 5, 2014
- Submitted: March 10, 2014
- Operation: Air carrier
- Aircraft: [N559AS](https://openairdocs.org/aircraft/N559AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35178
- Aircraft time: 27,952 hours, 8,367 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3989083
- Part serial: 1722
- Condition: Failed
- Location: A/C Bay
- Part time: 65,308 hours, 35,455 cycles
- 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/ASAA2014030507090

## Discrepancy

COCKPIT WAS VERY COLD, TURN TEMP CONTROL TO FULL WARM DUCT TEMP NEVER GOT OVER 30 TRIED IN OFF POSITON , NO CHANGE IN FULL WARM, ALL VENTS BLOWING COLD AIR.  ACFT GROUNDED.  DURING BITE TEST FOUND NR 1 TRIM AIR MODULATION VALVE INOPERATIVE.  R & R TRIM AIR MODULATION VALVE IAW AMM. 21-61-21.  VALVE OPS AND LEAKS CHECKED GOOD.

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