Status LED solid on with no flashing, furnace not responding or stuck

Steps to check:

• Verify thermostat settings: Ensure the thermostat is set to HEAT and the setpoint is above room temperature. Replace batteries if applicable.
• Check thermostat wiring: At the furnace, verify the W (heat call) wire is securely connected. Jumper R to W at the furnace terminal strip to simulate a call for heat. If the furnace starts, the thermostat or its wiring is faulty.
• Power cycle: Turn off power to the furnace for 30 seconds, then restore. This can clear minor control board lockups.

When to call a professional: If the furnace does not respond to an R-W jumper, the integrated furnace control board or safety circuits may be faulty and should be diagnosed by a technician.