# SDR CALA2013082190637

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 20, 2013
- Submitted: August 23, 2013
- Operation: Air carrier
- Aircraft: N175UA
- Make and model: Boeing 747422
- Aircraft serial: 24382
- Aircraft time: 90,135 hours, 10,142 cycles
- Engine: Pwa PW4056
- System (JASC): [4950 · APU Bleed Air System](https://openairdocs.org/jasc/4950)
- Part: Isolation Valve
- Part number: 39831051
- Part serial: 901992
- Condition: Faulty
- Location: Apu
- Stage of operation: IN
- 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/CALA2013082190637

## Discrepancy

APU BLEED VALVE WILL NOT OPEN.  REPLACED APU BLEED ISOLATION VALVE PER MM. CHECKED OKAY.

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