# SDR ASAA2021072335496

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 23, 2021
- Submitted: July 26, 2021
- Operation: Air carrier
- Aircraft: [N537AS](https://openairdocs.org/aircraft/N537AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35204
- Aircraft time: 35,394 hours, 10,256 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Control Valve
- Part number: 3989083
- Part serial: 16690
- Condition: Failed
- Location: Right Ecs Bay
- Part time: 35,429 hours, 10,263 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/ASAA2021072335496

## Discrepancy

RIGHT HAND PACK LIGHT ILLUMINATED ON RECALL. EXTINGUISHES WITH MASTER CAUTION RESET. GROUNDED - YES. ACCOMPLISHED PACK/ZONE TEMPERATURE CONTROLLER BITE TEST REF B737-800 AMM 21-61-00-700-806-002. R/H PACK BITE TEST FAILED FOR TCV. FOUND TCV TO BE SEIZED UP. REMOVED AND REPLACED TCV REF AMM 21-51-10-000/400-801. ACCOMPLISHED BITE TEST AGAIN, TEST PASSED. LEAK TEST PASSED. ALL GROUND VERIFICATION TESTS GOOD.

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