# SDR ASAA2022050738260

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 7, 2022
- Submitted: May 11, 2022
- Operation: Air carrier
- Aircraft: [N531AS](https://openairdocs.org/aircraft/N531AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35199
- Aircraft time: 42,252 hours, 12,231 cycles
- System (JASC): [3610 · Pneumatic Distribution System](https://openairdocs.org/jasc/3610)
- Part: Pneumatic System
- Part number: UNKNOWN
- Condition: Malfunctioned
- Location: Unknown
- Stage of operation: NR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2022050738260

## Discrepancy

DUCT PRESSURE SPLIT BETWEEN 15-20 PSI AT HIGH POWER SETTING PRESSURE SPLIT DROPS TO 5 PSI AT LOW POWER SETTING. GROUNDED - YES. RAN BOTH ENGINES AT IDLE. DUCT PRESSURE LOW ON #1 ENG. PERFORMED BLEED AIR HEALTH CHECK ON #1 ENG PER T/C NG-36WC-00001. FOUND CONTROL PRESS SENSE LINE LOOSE AT BLEED AIR REG. RETORQUED LINE AT BAR REF B737-800AMM 36-41-03. OPS CHECK GOOD. REF L/P 60475459 AND 6047560 FOR REPLACEMENT OF HIGH STAGE REG AND PRE COOLER CONTROL VALVE. ENG BLEED AIR CROSS OVER OPS CHECK GOOD. REF AMM 36-11-00.

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