# SDR ASAA0954619

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 1, 2009
- Submitted: March 6, 2009
- Operation: Air carrier
- Aircraft: [N577AS](https://openairdocs.org/aircraft/N577AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35186
- Aircraft time: 7,685 hours, 2,250 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3989083
- Part serial: 9750
- Condition: Failed
- Location: Cabin Temp
- Part time: 6,009 hours, 1,746 cycles
- Stage of operation: TX
- How discovered: O
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA0954619

## Discrepancy

DURING RECALL ON AFTER START CHECKLIST CONT CAB ZONE TEMP AND AIR CONDITIONING MASTER CAUTION ILLUMINATED.  ACCOMPLISHED QRH, OPS NORMAL.  PRIMARY COCKPIT TEMP CONT INOP.  FOUND ZONE TRIM MOD VALVE BAD.  INSTALLED NEW VALVE, OPS CHECKED GOOD.  NO FAULTS FOUND.

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