# SDR MISR202603027043

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 27, 2026
- Submitted: March 2, 2026
- Operation: Air carrier
- Aircraft: [N928QS](https://openairdocs.org/aircraft/N928QS), registered now
- Make and model: Cessna 680A
- Registry model: [Cessna 680A](https://openairdocs.org/model/cessna-680a) (OpenAirDocs)
- Aircraft serial: 680A0356
- Aircraft time: 2,904 hours, 1,915 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Control Valve
- Part number: 99125182
- Part serial: 3BY23F
- Condition: Defective
- Location: Cockpit Temp
- Stage of operation: CR
- How discovered: O
- Nature of condition: M
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/MISR202603027043

## Discrepancy

COCKPIT TEMPERATURE WAS UNCONTROLLABLE IN NORMAL OR MANUAL MODE. COCKPIT DUCT TEMPERATURE REACHED A HIGH OF 241°F. CORRECTIVE ACTION: VERIFIED DISCREPANCY. VISUALLY INSP'D AIR VENTS FOR BLOCKAGE, NO DEFECT. INSP'D COCKPIT ECS ROTARY SWITCH FOR EXCESSIVE PLAY OR STICKING, NO DEFECT. GAINED ACCESS BENEATH ROTARY SWITCH AND INSP'D WIRING, NO DEFECT. GAINED ACCESS TO AFT EQUIP BAY AND INSP'D ECS COMPS/DUCTS FOR LOOSE CONNECTIONS, SIGNS OF AIR LEAK, OBVIOUS DAMAGE. NO DEFECT. PERFORMED ARES DOWNLOAD AND SENT TO TEXTRON WHO VERIFIED NO FAULTY ACM DATA PRESENT, AND RECOMMENDED STARTING WITH R/R OF RH TEMP CONTROL VALVE. REMOVED/REPLACED RH TEMP CONTROL VALVE PER CE 680A AMM 21-10-20 AND PERFORMED FOLLOW ON OPERATIONAL TEST. LEAK/OPCHECK GOOD.

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