# SDR ASAA2021042534679

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 25, 2021
- Submitted: April 28, 2021
- Operation: Air carrier
- Aircraft: [N493AS](https://openairdocs.org/aircraft/N493AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41727
- Aircraft time: 18,451 hours, 5,914 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Valve
- Part number: 3989083
- Part serial: 11190
- Condition: Inoperative
- Location: Left Ecs Bay
- Part time: 38,138 hours, 15,085 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/ASAA2021042534679

## Discrepancy

ON MC RECALL - FLT DECK ZONE TEMP ILLUMINATED . RESET ON MC RECALL. TEMP SELECTOR OPERATED NORMALLY. GROUNDED - YES. PERFORMED BITE PROCEDURE REF B737-900 AMM 21-51-00, FLT DECK TRIM VALVE LT ILLUMINATED ON BOTH CONTROLLERS. REMOVED AND REPLACED FLT DECK ZONE TRIM AIR VALVE, LEAK AND OPS CHK GOOD REF AMM 21-61-21 AND AMM 21-51-00.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.