# SDR ASAA2021070235231

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 2, 2021
- Submitted: July 7, 2021
- Operation: Air carrier
- Aircraft: [N588AS](https://openairdocs.org/aircraft/N588AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35685
- Aircraft time: 48,549 hours, 14,452 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Control Valve
- Part number: 3966081
- Part serial: 2924
- Condition: Failed
- Location: Left Ecs Bay
- Part time: 48,613 hours, 14,118 cycles
- Stage of operation: TX
- How discovered: O
- Nature of condition: O
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021070235231

## Discrepancy

WITH POWER INCREASE UNUSUALLY HIGH AIRFLOW IN THE FLT DECK LEFT PACK GOES TO ABOUT 50 PSI AT 40% N1 WITH RIGHT STAYING ABOUT 32 PSI. GROUNDED - YES. REPLACED L/H PACK FLOW CONTROL VALVE REF B737-800 AMM 21-51-02 NO LEAKS NOTED, AT 40% N1 L PACK AT 31 PSI, R PACK 26 PSI.

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