# SDR ASAA2018111636856

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 13, 2018
- Submitted: November 16, 2018
- Operation: Air carrier
- Aircraft: [N596AS](https://openairdocs.org/aircraft/N596AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35688
- Aircraft time: 39,952 hours, 12,184 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Controller
- Condition: Malfunctioned
- Location: Temp
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2018111636856

## Discrepancy

ALL THREE ZONE TEMPERATURE CONTROLLERS "HYPER - SENSITIVE" THE SLIGHTEST TEMP ADJUSTMENT (HOT OR COLD) RESULTS IN VERY LARGE TEMP SWINGS/SPIKES. HOT OR COLD. GROUNDED - YES. COULD NOT DUPLICATE DISCREPANCY BOTH TEMP CONT LOG NO FAULTS AND A GO STATUS. REF B737-800 AMM 21-61-00-700-806. ACCOMPLISHED CABIN TEMP CTL OPS TEST REF AMM 21-61-00-700-806 ALL OPS NORMAL.

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