3 Reasons Your Furnace Will Not Stay Running

The furnace in your home needs to work when you turn it on, or there is little point in having one. Sometimes you need to have a heating repair technician come out to help troubleshoot and repair the system. There are some common reasons that you may be having trouble keeping the heating system running that the tech can check for you.

1. Faulty Thermocouple

If you have a gas furnace that has a pilot light on it, the thermocouple is a small device that detects whether or not the pilot light is lit. If the pilot goes out, the thermocouple will close the gas valve to the furnace so that no gas can flow into the system. 

If the gas continued coming into the furnace without interruption, the gas could ignite and cause an explosion when you attempted to relight the pilot. Sometimes the pilot will go out repeatedly as well, but if the pilot is not going out, it could be the thermocouple reporting no pilot and closing the valve when it should not be. The technician can test the thermocouple and replace it if it is bad.

2. Blower Motor Failure

The blower motor in your heating system moves air over the heat exchanger to heat the air going out to your home. If the blower motor stop working, the heat exchanger will get extremely hot because the heat if it producing is not being removed by the air passing over the exchanger. 

The heating system will detect the excess heat and shut the furnace down to protect the heat exchanger and the rest of the system. You can check for air movement from the heat ducts by merely putting your hand in front of the duct. If there is no air coming out, the blower motor may not be running at all. The technician can look further to determine what is causing the problem and to best fix it.

3. Fuel Line Issues

If the fuel to the furnace is cut off, the system is going to shut off and not restart. In some cases, the fuel line may have gotten bent or damaged outside the house, and the system is just not getting fuel to it. The technician can check the fuel flow to the system to determine if there is a problem and if they need to replace the line bring the fuel into your furnace.

Beyond the lack of fuel to the furnace, if the line is leaking, you could have a safety hazard that may result in a fire, contamination of the ground, or other complications, depending on the fuel you use in your furnace.