# SDR ASAA2022122841322

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 28, 2022
- Submitted: January 3, 2023
- Operation: Air carrier
- Aircraft: [N587AS](https://openairdocs.org/aircraft/N587AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35684
- Aircraft time: 53,961 hours, 15,707 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Modulating Valve
- Part number: 3989085
- Part serial: 23924
- Condition: Failed
- Location: Right Ecs Bay
- Part time: 17,397 hours, 5,067 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/ASAA2022122841322

## Discrepancy

RIGHT PACK LIGHT ILLUMINATED, RESET ON MASTER CAUTION RESET. GROUNDED - YES. CONFIRMED FAULT, R/H PACK LIGHT ILLUMINATES WHEN RECALLED. NO.2 PACK/ZONE TEMP CONTROLLER SHOWS HARD FAIL "TCV-2". REMOVED & REPLACED TCV-2 (V141) REF B737-800 AMM 21-51-10.

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