How to Fix / Troubleshooting

Safety: Turn off power and gas before removing burner access panels.

Steps to check:

Observe sequence: Restore power and call for heat. Note the order: inducer starts, ignitor should glow, gas valve clicks, burners light. Identify which step fails.
Ignitor inspection: If the ignitor never glows, inspect it for cracks or breaks and replace if damaged.
Flame sensor cleaning: If burners light briefly then go out, clean the flame sensor.
Pressure switch and venting: If the inducer stops before ignition, check pressure switch tubing and vent pipes for blockage.

When to call a professional: If the gas valve is suspected or ignition remains unreliable, have a Trane technician perform full diagnostics.

Thermostat calls for heat but furnace inducer starts and then shuts off without ignition

Possible Causes