# SDR ASAA2020062312827

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 21, 2020
- Submitted: June 23, 2020
- Operation: Air carrier
- Aircraft: [N442AS](https://openairdocs.org/aircraft/N442AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 43293
- Aircraft time: 25,487 hours, 8,185 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3989085
- Part serial: 35933
- Condition: Faulty
- Location: Left Ecs Bay
- Stage of operation: TX
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020062312827

## Discrepancy

AFTER START MASTER CAUTION RECALL CONT CAB ZONE TEMP ILLUMINATED. EXTINGUISHES UPON RESET. GROUNDED - YES. PERFORMED PACK/ZONE TEMP CONT BITE TEST REF B737-900 AMM 21-61-00. FLT DECK TRIM VALVE FAULTED. REMOVED & REPLACED CONT CAB TAV REF AMMM 21-61-000 & 21-61-21-400. OP'S AND LEAK CHECK GOOD.

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