If your furnace won’t turn on, it might be simple to fix. You may be able to troubleshoot the problem yourself with this step-by-step guide.
If there’s no heat:
- Make sure the thermostat is set to heating mode.
- Check that power switch is set to the On position.
- If it’s on but not working, there could be a short in the breaker box. If you’ve tried all of these, it could be the thermostat.
When the furnace won’t fire:
- If there’s a pilot light, make sure that it’s lit and touches the thermocouple.
- If it’s lit but the burners don’t heat, feel the side of the furnace. If it’s cool, the problem might be the thermostat, gas valve or control board.
- Make sure that the gas valve is on and that there’s enough fuel.
When the furnace won’t stay on:
- The condensate reservoir might be full, the pump may be broken or the drain might be plugged. If it’s unable to be cleared, it’s likely the pump. It could be dirty, which will prevent it from getting enough air, and it’ll shut down.
If the furnace won’t turn on still, here are some other factors that could affect furnace performance:
- The inducer motor doesn’t run: The problem could be in the motor or the control board.If the inducer motor is running, check to see that the pilot light tries to ignite. Some use a spark ignition, in which case you’ll hear a clicking sound.
- If the pilot goes out, the pilot assembly or flame sensor might be dirty. See if the hot surface igniter is coming on. If not, the control board may have a problem. Also, check to see if the flue is blocked.
- Sometimes, when all else fails, the problem is in the way that the furnace was originally installed.
For more furnace troubleshooting tips, contact us at All Temp Co., Inc. Air Conditioning & Heating. We’re happy to help homeowners throughout the greater Charlotte and Harrisburg areas.