# SDR ASAA2016071517374

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 15, 2016
- Submitted: July 19, 2016
- Operation: Air carrier
- Aircraft: [N529AS](https://openairdocs.org/aircraft/N529AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35198
- Aircraft time: 24,804 hours, 7,441 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Modulating Valve
- Part number: 3989083
- Part serial: 13497
- Condition: Malfunctioned
- Location: Ac Bay
- Part time: 24,844 hours, 7,455 cycles
- Stage of operation: NR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2016071517374

## Discrepancy

A/C PACK LIGHT ILLUMINATED FOR NR 2 PACK.  EXTINGUISHES WITH M/C RESET.  ACFT GROUNDED.  R & R ZONE TRIM AIR MODULATING VALVE IAW AMM 21-61-21, PERFORMED ZONE TRIM AIR MODULATING VALVE INSTALLATION BITE TEST, NO FAULT NOTED, AND LEAK CHECK FOUND NORMAL IN REF AMM 21-61-21, STEP 3.  THIS CLEAR MEL 21-32B.

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