Known issue: Trane / American Standard 4YCZ5 gas/electric packaged units, gas valve can open (2025 recall)

In July 2025 Trane Technologies and the CPSC recalled about 4,790 two-stage gas/electric packaged units (models 4YCZ5024F1060A, 4YCZ5036F1070A, 4YCZ5036F1090A, 4YCZ5048E1090A, 4YCZ5048E1115A, specific serial ranges, sold January 2024 to March 2025) because the gas valve could open unexpectedly. Owners were told to stop using heating mode; the installing dealer inspects and replaces the ignition board free. Serial ranges differ slightly between notices, so confirm with Trane.

Cross-checked ~20 min easyBrands: Trane, American Standard

Before you start

If you smell gas: leave the area, no switches or flames, call the gas utility from a safe place
Do not service the gas valve, ignition control or burners on these units: dealer / licensed gas technician only

Diagnostic steps

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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