Gas furnaces always run on heating cycles. Each cycle is the time from when the furnace turns on until the thermostat registers the correct temperature and signals the furnace to shut off. If you ever notice that your furnace is running for a much shorter or longer time than normal, it indicates there is some issue preventing your heating system from working correctly. With that in mind, here is a quick overview of the average length of a furnace’s heating cycle and also what it means if your furnace is cycling on and off too slowly or too quickly.

Average Heating Cycle Length

If your furnace is well maintained and working properly, it will typically perform two to three heating cycles per hour with each cycle lasting for around 10 to 15 minutes. That being said, there are a few different factors that can affect either the length of each cycle or how many cycles the furnace has per hour.

Outdoor temperature is obviously one of the biggest factors since this will affect both how quickly your home cools down and how much heat is needed to bring the temperature back up. In below-zero weather when much more heat is needed, it isn’t uncommon for each heating cycle to last up to 20 or 30 minutes and for the furnace to only ever stay off for five to 10 minutes before starting the next cycle.

Another factor is the difference between the thermostat setting and the indoor temperature when the furnace turns on. If the indoor temperature is more than 2 or 3 degrees below the thermostat setting, the initial heating cycle will be longer since more heat is needed to bring the temperature back up.

Short Cycling and Long Cycling

Short cycling is when the furnace only ever runs for a few minutes and then shuts off, sometimes even before the thermostat registers the correct temperature. This issue most commonly results from the furnace being oversized and much bigger than is needed to effectively heat the home. Short cycling can also occur because the furnace is overheating due to insufficient airflow or a number of other potential reasons.

If your furnace constantly runs for longer than 20 or so minutes even in milder weather, it indicates that there is some issue preventing it from heating efficiently and effectively. The only real way to overcome issues with either short cycling or long cycling is to have your furnace professionally inspected as this is the only way to determine what exactly is causing the problem.

If you’re experiencing any issues with your furnace, Advanced Comfort Solutions is ready to help. We maintain and install all brands and types of furnaces, and we also specialize in furnace replacement. Our certified technicians also install, repair, and maintain cooling systems, ductwork, indoor air quality equipment, and other HVAC units. We also design and install full HVAC systems for new residential construction projects. If you need any residential or commercial HVAC service in Cheyenne, contact us today.

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