Reasons A Furance Won't Stop Running And Ways This Problem Can Be Fixed

29 January 2015
 Categories: , Articles


When it's cold outside your furnace may run a lot, but it shouldn't run constantly. If a furnace will not shut off, it typically means there is a problem. If you want to diagnose the problem yourself, here are some tips to help you find out what the problem might be. If you cannot find the problem, or if you do not know how to fix it, you can hire a furnace repair company to do this for you.

Steps To Take To Find The Problem

Here are two things you can do to try to locate the problem your furnace is experiencing:

Step 1: Check the Thermostat

The thermostat is the device that controls the furnace by letting it know when to come on and when to shut off. If there is a communication problem between the thermostat and the furnace, it could cause your furnace to continue running even when it doesn't need to.

To detect if there is a problem with the thermostat, turn it down a few degrees, or shut it off completely. When you do either of these things, the furnace should stop running. If it does, then it may just be extremely cold and your furnace might need to keep running to keep up with the demand set on the thermostat.

Step 2: Shut the Furnace Off Manually

If you are still not able to shut the furnace off after completing the first step, you could manually shut it off. You will need to locate the power button on the furnace in order to manually make it stop running, and when you switch this button or lever, the furnace should instantly stop.

When you must manually shut off your furnace, the issue you are having could be caused by one of the following reasons:

  • Bad blower motor fan – This is the fan that pushes the heat created in the furnace into your house.
  • Gas supply – If the furnace is not getting gas for some reason, the blower might keep running because it senses that it needs to produce heat.
  • Dirty furnace filter – If the filter is extremely dirty, the furnace may keep running, or it might cycle on and off.

If you cannot find the power switch on the device, you could always shut it off by flipping the breaker that controls the furnace.

How To Fix The Problem

There are certain types of furnace repairs that can wait, but this is not one of them. A furnace that will not shut off is not a good problem to have. If you unable to diagnose or fix the problem, call a professional. They will check the furnace filter first and will then use one of the following methods to repair your furnace:

  • Replace the thermostat – If the thermostat is no longer working, replacing it will usually solve the problem.
  • Rewire the thermostat – If the repair technician finds that the wiring is bad, he can replace it, which will cause the furnace to start and stop as needed.
  • Replace the thermocouple – When a furnace is not getting gas, it is usually because the thermocouple is corroded or not functioning properly.
  • Replace the blower motor – If the technician has ruled out all the other problems, the problem is most likely caused by a faulty motor blower, which will need to be replaced.

Until the problem is repaired by someone from a site like, you will have to keep your furnace shut off. If you have questions about your furnace or if you would like to schedule repairs, call a company that offers furnace repair services in your area today.