# SDR ASAA2019110181149

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 28, 2019
- Submitted: November 6, 2019
- Operation: Air carrier
- Aircraft: [N531AS](https://openairdocs.org/aircraft/N531AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35199
- Aircraft time: 36,692 hours, 10,757 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Control Valve
- Part number: 3989083
- Part serial: 9186
- Condition: Failed
- Location: Lt A/C Pack
- Part time: 47,841 hours, 14,462 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/ASAA2019110181149

## Discrepancy

WHEN MASTER RECALL IS PUSHED, CONT CAB "ZONE TEMP" LIGHT ILLUMINATES. "ZONE TEMP" LIGHT EXTINGUISHES WHEN MASTER CAUTION LIGHT IS RESET. GROUNDED - YES. CONFIRMED FAULT, "CONT CAB ZONE" TEMP LIGHT COMES ON WHEN RECALL PRESSED. R/H PACK/ZONE TEMP CONTROLLER BITE SHOWS HARD FAIL "FLIGHT DECK" TCV (V143). REMOVED & REPLACED TCV REF B737-800 AMM 21-61-21, R/H PACK/ZONE TEMP CONTROLLER BITE TEST NML REF AMM 21-61-00-700-806-002. L/H PACK/ZONE TEMP CONTROLLER SHOWS NO FAULTS.

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