# SDR CALA2026061217064

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 9, 2026
- Submitted: June 18, 2026
- Operation: Air carrier
- Aircraft: [N27276](https://openairdocs.org/aircraft/N27276), registered now
- Make and model: Boeing 737-8
- Registry model: [Boeing 737-8](https://openairdocs.org/model/boeing-737-8) (OpenAirDocs)
- Aircraft serial: 64611
- Aircraft time: 12,278 hours, 4,163 cycles
- System (JASC): [3040 · Windshield/Door Rain/Ice Removal](https://openairdocs.org/jasc/3040)
- Part: Controller
- Part number: 8300027904
- Part serial: 07600
- Condition: Faulted
- Location: Zone 200
- Part time: 6,754 hours, 2,276 cycles
- Stage of operation: NR
- How discovered: O
- Nature of condition: B
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026061217064

## Discrepancy

L FWD WINDOW HEAT  OVERHEAT CAUTION WOULD NOT RESET UPON ARRIVL TO THE FLIGHT DECK, FOUND C/B B21 ON THE P6-5 TRIPPED. CLOSED C/B, BREAKER DID NOT TRIP AGAIN. TURNED WINDOW HEAT SWITCH ON, FOUND ON LIGHT ILLUMINATED SHORTLY FOLLOWED BY BOTH LIGHTS ILLUMINATING. AFTER 10 SECONDS, ONLY OVERHEAT LIGHT ILLUMINATED. DURING BITE OF WHCU 1, NOTICED ELECTRICAL BURNING SMELL EMINATING FROM THE WHCU. REMOVED AND REPLACED WHCU 1 REF AMM 30-41-11-400-801. INSTALLATION TEST PASSED. OPS CHECK NORMAL AT THIS TIME.

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