# SDR ASAA2020020542084

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 4, 2020
- Submitted: February 6, 2020
- Operation: Air carrier
- Aircraft: [N409AS](https://openairdocs.org/aircraft/N409AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41733
- Aircraft time: 28,007 hours, 9,070 cycles
- Engine: Cfmint CFM567B27E
- System (JASC): [7532 · Compressor Bleed Valve](https://openairdocs.org/jasc/7532)
- Part: Regulator
- Part number: 1074926
- Part serial: 15204
- Condition: Failed
- Location: Nr 1 Engine
- Part time: 28,007 hours, 9,070 cycles
- Stage of operation: TX
- 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/ASAA2020020542084

## Discrepancy

WITH BOTH ENGINES RUNNING, POWER AT IDLE, BOTH PACKS IN AUTO, LEFT DUCT PRESSURE READS 10 PSI. ENGINE ANTI ICE OFF AS WELL. GROUNDED - YES. PERFORMED DUCT PRESSURE LOW FAULT ISOLATION REF B737-900 FIM 36-10 TASK 804. REMOVED AND REPLACED BLEED AIR REGULATOR REF B737-900 AMM 36-11-03/401. PERFORMED ENGINE RUN REF POWER ASSURANCE CHECK REF AMM 71-00-00-700. OPS CHECK WAS NORMAL.

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