A furnace, like all other types of complicated appliances, can be susceptible to all sorts of operational issues. One of the most common problems with central furnaces is constantly turning on and off, otherwise known as cycling. A cycling furnace can greatly increase your energy bills while failing to properly heat your home, reducing your overall comfort levels. Thankfully, there are a few things you can do to a furnace that keeps cycling to try and get it to work as it is supposed to.
Clean the Air Filter
The most common reason for a furnace to start cycling is also the easiest to fix. An air filter that is clogged with dust and debris can reduce the amount of air that flows through your furnace, causing hot air to begin to build up around the thermostat that regulates the furnace's temperature. Your furnace will think that the house is as warm as it should be and turn itself off, leaving the area around your furnace very warm but the rest of your home cold. All you have to do is remove the furnace's air filter from its casing (usually can be done by hand, but some models require a screwdriver to loosen the casing) and wipe away the built up dust and material.
Another common reason for your furnace to begin cycling is if there is an issue with your thermostat. Check to make sure that all of the settings are correct on your thermostat, and that it is not exposed to an additional heat source, such as sunlight or a space heater. Then, you should check its accuracy by hanging a thermometer on the wall right next to the thermostat. Let it sit for an hour or two, and check the readings on both. They should be within a few degrees of each other, if not the same, so if there is a significant difference between the readings, you have an issue with your thermostat and should get it replaced. This should solve any sort of cycling issues that you have been experiencing, and improve the overall efficiency of your furnace as well.
Finally, your furnace may be constantly cycling on and off because it is simply not the right size for the amount of space that you are trying to heat. A furnace that is too small for your home will be constantly turning on and off as it tries to maintain a temperature that it is simply not efficient or powerful enough to maintain. You should get a home appliance repair service, such as AAA Home Services, to come in and inspect your unit if you suspect that this is the case, as you may want to consider replacing your furnace in order to save money on your energy bills.