# SDR AALA2020080399005

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 24, 2020
- Submitted: August 3, 2020
- Operation: Air carrier
- Aircraft: [N964AN](https://openairdocs.org/aircraft/N964AN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 30093
- Aircraft time: 57,497 hours, 23,786 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Control Valve
- Part number: 3989055
- Part serial: 29733
- Condition: Defective
- Location: Zone 100 - Fuse
- Stage of operation: DE
- How discovered: V
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA2020080399005

## Discrepancy

AIRCRAFT WAS GROUNDED: DESCENDING THRU FL 330 MASTER CAUTION AUTO FAIL LIGHTS ILLUMINATED, ACCOMPLISHED QRH PROCEDURE - MODE SELECTOR - ALTN - AUTO FAIL LIGHT EXTINGUISHED. NORMAL PRESSURIZATION. REPLACED CABIN PRESSURE CONTROLLER #2 PER AMM 21-31-01 AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK. ALSO REPLACED RIGHT HAND PACK TEMPEATURE CONTROL VALVE PER AMM 21-51-10 AS A PRECAUTION. ACCOMPLISHED A SATISFACTORY LEAK AND OPERATIONAL CHECK (NOTE: A SIMILAR ISSUE WITH THE CABIN PRESSURTIZATION THAT OCCURED ON THE SAME DAY. THE REPLACEMENT OF CABIN PRESSURE CONTROLLER #2 AND THE RIGHT HAND PACK TEMPEATURE CONTROL VALVE CORRECTED THAT ISSUE ALSO.

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