# SDR ASAA2023042943040

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 29, 2023
- Submitted: May 1, 2023
- Operation: Air carrier
- Aircraft: [N531AS](https://openairdocs.org/aircraft/N531AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35199
- Aircraft time: 45,519 hours, 13,195 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3989085
- Part serial: 28879
- Condition: Faulty
- Location: Left Ecs Bay
- Part time: 18,855 hours, 6,127 cycles
- 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/ASAA2023042943040

## Discrepancy

"ZONE TEMP" AMBER ANNUNCIATOR ON OVERHEAD PANEL CONT CAB. EXTINGUISHES ON M.C RESET. GROUNDED - YES. R/R ZONE TRIM AIR MODULATING VALVE (V00143) IAW B737-800 AMM 21-61-21-400-801.

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