# SDR SCNA20250818323

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 16, 2025
- Submitted: August 18, 2025
- Operation: Air carrier
- Aircraft: [N831SY](https://openairdocs.org/aircraft/N831SY), registered now
- Make and model: Boeing 737-83N
- Registry model: [Boeing 737-83N](https://openairdocs.org/model/boeing-737-83n) (OpenAirDocs)
- Aircraft serial: 28249
- Aircraft time: 69,001 hours, 30,921 cycles
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Filter
- Condition: Odor
- Location: Zone 100
- Stage of operation: DE
- 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/SCNA20250818323

## Discrepancy

DEFECT 802437: VERY PUNDJENT MUSTY SMELL COMING THROUGH THE AIR VENTS ON DECENT AND ONLY ON DESENT	RESOLUTION: REMOVED AND REPLACED LEFT & RIGHT RECIRCULATION HEPA FILTERS. REF. 21-25-01-400-801. REMOVED AND REPLACED EQIP COOLING FAN FILTER REF 27-21-01-400-801. PERFORMED OPS CHECK ON B OTH. NO ISSUE FOUND.

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