Why Does My Furnace Keep Shutting Off?

Do you have a fickle furnace? One that turns on and off repeatedly – leaving you in the cold in your very own home?

This is called short cycling, and it is a serious issue that can cause the costly and premature breakdown of your furnace. This inefficiency can also increase your energy bills dramatically.

A properly working furnace should turn on and off approximately three to eight times per hour depending on the interior of your home, outside temperatures and other variables.

If the furnace comes on and off more frequently than this, give the Vredevoogd team a call so that we can help you decide whether you need furnace repairs or a replacement. After all, replacing a furnace is quite expensive, so let us help you determine what may be going wrong and fix it.

Cause #1: Your air filter may be clogged. Filters should be replaced every 90 days. When they are not replaced at regular intervals, the filters block proper air flow which cuts off the stream of heat into your home. In time, the clogged filters can overheat, eventually turning off your furnace with the built-in high-limit switch. Turn the furnace off, replace the filter and turn it on again.

Cause #2: Check the thermostat. Thermostats can go bad over time, so rule this out as a source of the issue if your furnace is shutting on and off. To do this at home, remove the thermostat face plate and use alligator clips to touch the white and the red wires together for a few minutes. If the furnace turns on and runs smoothly, it is time for a new thermostat.

Cause #3: Check the blower motor. This will not be the cause for most modern furnaces, but older models may run while the blower motor is off which does not allow air to blow over its heat exchangers. To check whether this may be an issue, put your hand up to the vent and see if a good air flow is coming out. If not, you will need to enlist an HVAC technician for a detailed examination.

Cause #4: Your furnace may be too big. If your unit is not the right size for your home, it will come on, heat your home quickly then shut itself off. Or, it may overheat because there is nowhere to push the hot air. This can be the most expensive fix because you will need a new unit that is better suited for your home.

Call Vredevoogd Heating & Cooling for all your plumbing, heating, & cooling needs. In the greater West Michigan, Lakeshore, and surrounding areas call: 844-HVAC-365