When it comes to home heating and cooling, furnaces are essential to keeping your home comfortable throughout the year.

Unfortunately, like any other major appliance, furnaces are prone to malfunction. Identifying and resolving common furnace problems can help ensure your furnace works safely and efficiently.

If you experience any of the following signs, it’s time to have your furnace inspected.

  • Blower Fan Problems

Blower fan problems are one of the most common furnace problems. If you notice that your blower fan is not operating properly, or if it does not, this can cause your furnace to stop working. If your blower fan is not working correctly, you may notice that your furnace does not blow warm air into the home. This can also cause moisture to build up in the ductwork and walls of your home.

  • Thermostat Problems

Sometimes, your home’s furnace simply isn’t working properly. Maybe the thermostat is misreading the temperature, or the heat is coming on too late or too early. Whatever the case, it’s important to check your thermostat before you call a professional.

  • Clogged Filter Problems

If your furnace is blowing warm air or not blowing air at all, the problem could be a clogged filter. A clogged filter can cause the blower to overheat and shut off, stopping the airflow through your furnace. 

  • Furnace Pilot Light Problems

If your furnace won’t turn on, there’s a good chance that the pilot light is out. An inefficient burn can occur when there isn’t enough fuel or oxygen to keep a fire going. You can try to re-light it yourself if you know how. If not, call a technician to re-light it for you.

  • Flame Sensor Problems

If the flame sensor is broken, it can cause problems with your furnace. This sensor is usually located near the pilot light and turns on when enough oxygen is in the system to keep it burning. If this sensor is broken, it won’t turn off even when there’s plenty of oxygen, which will cause your furnace to run constantly.

  • Inducer Motor Problems

In a gas furnace, the inducer motor causes air to flow through your home. The inducer motor turns on once the pilot light has been lit and burns until enough heat has built up in your system so that it doesn’t need any more air flowing through it. If this motor stops turning on, you’ll have no airflow and won’t be able to heat your home.

  • Ignition Control Module (ICM) Problems

In a gas furnace, the ignition control module turns on your gas valve and lights the pilot light once you’ve turned on the power switch. If this module stops working, then your furnace won’t be able to get its fuel source. This will cause it to shut down until someone comes out and fixes the problem.


It is important to be aware of the most common furnace problems to ensure the longevity of your system and to keep it running efficiently. By taking the time to identify and fix these issues, you can help your furnace run at its best. If you have any questions about your furnace or need more information, don’t hesitate to contact us today.

Thompson Heating & Cooling is a professional HVAC company that offers furnace repair services to customers in La Grange, Louisville. We are dedicated to providing top-quality work at affordable prices, which is why so many people trust us.