Posted on

How to Troubleshoot a Control Board on a Furnace

Problem: How do I know if my control board is good or bad? My furnace and air conditioner will not work at all?

Answer: We have this question asked many times. My furnace and blower will work or come on no matter what I do? How do I check to see if my control board is the problem? We have a really good YouTube Video below made by Word of Advice TV on how to troubleshoot a furnace’s control board. Thanks so much to Word of Advice TV for making this great troubleshooting video! I would like to suggest that you check with a volt-meter set to “Volts AC” and make sure all your safety controls are closed when the draft inducer is running and the thermostat is calling for heat. We sell a really good volt meter on the following page: Please click here if you would like to see a really nice multimeter that we sell. If any of the safety controls like the furnace’s limit, rollout switches or pressure switch are open then the control board will not allow the furnace to start. Here is a picture of two limits and one rollout switch.


If the furnace’s draft inducer will not start or if the blower motor will not start then this could very well be a control board problem. I hope the YouTube video below will help you troubleshoot your furnace’s control board. We sell many different brand name control boards on the following page: Please click here if you would like to see the control boards that we sell. 

If you have any questions please email us anytime. If you would like for us to find out which part or parts your furnace uses then please send us your furnace’s name brand and model number to our email address:

We Would Love to Help You Out and Earn Your Business!