# SDR DALA2025040202491

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 1, 2025
- Submitted: April 2, 2025
- Operation: Air carrier
- Aircraft: [N544US](https://openairdocs.org/aircraft/N544US), registered now
- Make and model: Boeing 757251
- Aircraft serial: 26491
- Aircraft time: 87,904 hours, 28,850 cycles
- System (JASC): [2100 · Air Conditioning System](https://openairdocs.org/jasc/2100)
- Part: Heat Exchanger
- Part number: 1942723
- Part serial: 103525
- Condition: Leaking
- Part time: 94,932 hours, 35,142 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2025040202491

## Discrepancy

SHIP 5644 -ATB/PRES/DE- DUE TO CABIN PRESSURE CONTROL ISSUE. CORRECTIVE ACTION: R/R OUTFLOW VALVE, CABIN PRESS CONTROL PANEL, AUTO CABIN PRESSURE CONTROLLER 1, AND RIGHT HEAT EXCHANGER. PERFORMED SINGLE PACK CONFIDENCE CHK.

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