# SDR UALA2011080504082

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 4, 2011
- Submitted: September 6, 2011
- Operation: Air carrier
- Aircraft: N529UA
- Make and model: Boeing 757222
- Aircraft serial: 25019
- Aircraft time: 67,446 hours, 24,955 cycles
- Engine: Pwa PW2037
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3987865
- Part serial: 273
- Condition: Malfunctioned
- Location: Ac Bay
- Stage of operation: CL
- 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/UALA2011080504082

## Discrepancy

FLT DECK TEMP WENT FULL HOT ON CLIMBOUT.  STANDBY NO HELP.  TRIM AIR OFF REGAINED CONTROL.  AFTER FUTHER TROUBLESHOOTING FOUND SYSTEM NEEDS TRIM AIR VALVE 643-9023 CONFLICTING WITH OTHER WORK.  RPL FLT DECK TRIM AIR MODULATING VLV.

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