System Diagnosis
Pressure switch failure (venting/inducer problem). The pressure switch did not close or reopen appropriately.
Trane | Furnaces
Error Code 3 Flashes
Troubleshooting guide for the Trane Furnaces system fault 3 Flashes.
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
Potential Causes & Solutions
- Inspect the vent/exhaust pipe for blockages (e.g.
- ice, debris) and ensure the inducer fan starts.
- Clean out condensate if applicable.
- Replace the pressure switch if it’s defective.
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