# SDR ASAA2012072392610

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 2, 2012
- Submitted: July 31, 2012
- Operation: Air carrier
- Aircraft: [N594AS](https://openairdocs.org/aircraft/N594AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35191
- Aircraft time: 16,632 hours, 5,190 cycles
- Engine: Cfmint CFM567B27
- System (JASC): [3610 · Pneumatic Distribution System](https://openairdocs.org/jasc/3610)
- Part: Sensor
- Part number: 1296663
- Part serial: 13473
- Condition: Malfunctioned
- Location: Duct Pressure
- Part time: 14,541 hours, 4,611 cycles
- Stage of operation: NR
- How discovered: O
- Nature of condition: N
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2012072392610

## Discrepancy

DUCT PRESSURE DIFFERENTIAL GREATER THAN 20 PSI (APPROX 22).  LT PACK LOWER THAN RIGHT PACK.  LT 23PSI.  RIGHT 45PSI.  PERFORMED ENGINE BLEED AIR SYSTEM HEALTH CHECK ON NR 1 ENGINE, NO FAULTS FOUND, LEAK CHECKED OK.  NR 1 ENGINE HAD BLEED TRIP.  PRECOOLER CONTROL VALVE AND PRECOOLER CONTROL VALVE SENSOR WERE REPLACED WITH REPAIR CONFIRMATION AND FVR FLIGHT CONFIRMING NORMAL BLEED AIR OPERATION.

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