# SDR ASAA2021030634245

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 6, 2021
- Submitted: March 9, 2021
- Operation: Air carrier
- Aircraft: [N431AS](https://openairdocs.org/aircraft/N431AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 43255
- Aircraft time: 27,762 hours, 8,957 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Ecs
- Condition: Unknown
- Location: Primary
- 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/ASAA2021030634245

## Discrepancy

FLIGHT DECK PRIMARY TEMP CONTROL INOP. GROUNDED - YES. ACCOMPLISHED `PZTC BITE TEST REF B737-900 AMM 21-61-00-700-806-002. LAST FLIGHT LEG HISTORY SHOWED FAULT FOR FLT DECK TRIM VALVE. PREV FLT LEG HISTORY SHOWED NO FAULTS. NO FAULTS SHOWED UPON VERIFICATION.

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