Here’s How to Determine If Your Furnace Is Short Cycling

Fall is finally here, and for many homeowners throughout North America, the furnaces are already switching on. We hope your furnace fired up without a hitch this year, because early fall is one of the busiest times of year for furnace service. After lying dormant during the cooling season, some furnaces aren’t quite ready to get the job done—especially if they haven’t been tuned up for the winter.

One common furnace problem is called “short cycling”—that’s when the furnace starts and stops too quickly and too often. Short cycling is a problem most often associated with air conditioners, but furnaces can suffer from it as well and for similar reasons. Here are the three primary reasons why your furnace may be short cycling, as well as tried-and-true fixes for this annoying and potentially damaging issue.

Common Causes of Furnace Short Cycling

If you just installed a new furnace and are experiencing short cycling right off the bat, this may be the news you don’t want to hear. Short cycling can be caused by a furnace that is just too powerful for your space.

That’s a mistake that can cost you dearly in the long run.

Every homeowner wants their furnace to warm up their rooms quickly, but given the choice, most would prefer that they heat spaces in an economical manner. That’s why it’s important for HVAC installers to match the size of the furnace to the space. If the furnace is oversized, it will consume far too much energy while heating your home to your thermostat setting. This overpowered process may also mean that warm air doesn’t get distributed properly, which will cause the furnace to turn on again after too short an interval.

This is bad news in more ways than one. The short cycling itself is likely to drive up your monthly energy bills, but it also makes for more wear and tear on your HVAC fan. This can mean servicing or replacing the fan ahead of schedule, all while you pay more per month for an inefficient system. If you’re not sure whether your furnace is short cycling for this reason, reach out to One Hour’s top technicians.

Possibility of Furnace Overheating

It’s also possible that your furnace is shutting itself down prematurely to protect itself from damage related to overheating. When a furnace overheats, it creates the possibility of cracks in the heat exchanger, which can be deadly serious. Cracked heat exchangers can cause carbon monoxide to leak into a home, presenting an immediate risk to life. Frequent overheating can contribute to cracks even when the furnace short cycles to save itself so it’s important to call in the technicians if you think this may be happening.

Overheating is usually a consequence of restricted airflow, which can trap hot air in the area closest to the heat exchanger. This may be because of a dirty air filter, blocked interior vents, or even a blocked exhaust vent on the roof. If you’re unsure where the problem lies, a licensed HVAC technician can help you track it down.

Take Control with the Thermostat

Your furnace gets its instructions from your thermostat. If the thermostat is malfunctioning, just about anything can happen. Your furnace might start short cycling, it might stay on all the time, or it might refuse to start altogether. If you think the problem is with your thermostat, a qualified technician can tell you for sure.

Even if your thermostat is working, it could cause the furnace to short cycle if it’s improperly installed close to a significant heat source, such as a stove or a large sun-facing window. This can trick the thermostat into thinking the home is too hot, which can kick off a series of short cycles.

Short cycling is a serious energy efficiency problem that also increases the physical wear on your HVAC system. If you’re struggling to get this issue under control, contact your local One Hour Heating & Air Conditioning for trusted furnace repair and maintenance services today.