# SDR ASAA2022120841088

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 8, 2022
- Submitted: December 12, 2022
- Operation: Air carrier
- Aircraft: [N928AK](https://openairdocs.org/aircraft/N928AK), registered now
- Make and model: Boeing 737-9
- Registry model: [Boeing 737-9](https://openairdocs.org/model/boeing-737-9) (OpenAirDocs)
- Aircraft serial: 44099
- Aircraft time: 2,940 hours, 858 cycles
- System (JASC): [3010 · Airfoil Anti/De-ice System](https://openairdocs.org/jasc/3010)
- Part: Anti-Ice Valve
- Part number: UNKNOWN
- Condition: Unknown
- Location: Unknown
- Stage of operation: NR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2022120841088

## Discrepancy

LEFT WING ANTI ICE VALVE DID NOT EXTINGUISH WHEN ANTI ICE VALVE TURNED ON. LEFT WING REMAINED ICED UP, RIGHT WING WAS CLEAN. GROUNDED - YES. IT WAS A HARD FAIL ON GND AS WELL WHEN CREW SHOWED ME. BUT AFTER TRYING IT AGAIN THE L WING LT WENT OUT AFTER 15 SEC. A THIRD TRY AFTER BEING ON THE GROUND FOR 20 MIN. - THE L WING & R WING ANTI-ICE VALVE LT'S COME ON SIMULTANEOUSLY. SUSPECT FROZEN VALVE OR STICKING. MANUALLY OPERATED VALVE, OPS NORMAL. PERFORMED "WING THERMAL ANTI ICE VALVE HEALTH CHECK" REF B737-9 AMM 30-11-11. PERFORMED STEPS A-E. OPS CHECK NORMAL. VERIFIED RH FLOW CONTROL & SHUTOFF VALVE CANNON PLUGS INSTALLED/CONNECTED. NO FAULTS PRESENT AT THIS TIME.

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