# SDR ASAA2021101636340

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 16, 2021
- Submitted: October 20, 2021
- Operation: Air carrier
- Aircraft: [N589AS](https://openairdocs.org/aircraft/N589AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35686
- Aircraft time: 50,427 hours, 14,880 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Modulating Valve
- Part number: 3989085
- Part serial: 24061
- Condition: None
- Location: Left Ecs Bay
- Part time: 20,257 hours, 5,652 cycles
- Stage of operation: TX
- 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/ASAA2021101636340

## Discrepancy

LEFT PACK LIGHT ILLUMINATED AFTER ENGINE START, RESET WITH MASTER CAUTION. GROUNDED - YES. REMOVED AND REPLACED L/H PACK TEMPERATURE CONTROL VALVE REF B737-800 AMM 21-51-10. OPS CHECK GOOD. GROUND VERIFICATION SUCCESSFUL.

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