Most furnaces kick on and off between three to eight times an hour, depending on things like outdoor air temperatures, the furnace's age, and how much insulation you have. That's why, instead of asking how often a furnace should cycle, it's best to stay alert to changes in how your furnace is running.
It's normal for a furnace to turn on and off periodically. They are designed to cycle on and off, but a standard home furnace should only turn on and off between three to eight times per hour. That means normal heating cycles last from seven to 20 minutes.
Typically, a furnace should cycle three to eight times per hour. While furnace cycling is normal, frequent cycling can indicate that your heating is struggling to keep up.
This is commonly caused by a dirty air filter. Once high temperatures are reached within the equipment, the limit switch shuts down the heating cycle for safety reasons. Then the furnace must cool down before another cycle starts – but the issue just happens again.
With an effective air delivery system and a well-insulated home, this should be long enough to establish your preferred temperature throughout the building. After resting for approximately five to 10 minutes, your furnace will likely cycle on again.
Most furnaces kick on and off between three to eight times an hour, depending on things like outdoor air temperatures, the furnace's age, and how much insulation you have. That's why, instead of asking how often a furnace should cycle, it's best to stay alert to changes in how your furnace is running.
On average, furnaces should kick on and turn off anywhere from three to eight times per hour. However, if your furnace turns on and off more frequently, don't assume the furnace is short cycling just yet.
If the time between cycles is less than five minutes, the furnace is most likely short-cycling. Heating cycles that run for shorter periods of time produce more frequent heating cycles. Depending on the outside temperature and how well-insulated your home is, these short cycles may occur five to eight times per hour.
If your furnace turns on, and off, and back on again in a seemingly endless loop, you're experiencing short cycling. Essentially, short cycling occurs when the system cannot complete a full heating cycle. There's no one cause of short cycling, but with some troubleshooting you can get to the bottom of the issue.
HVAC maintenance companies explain that a furnace will normally perform an average of two to three cycles in an hour, with each cycle lasting 10 to 15 minutes. But to keep temperatures at a comfortable level during cold weather, a furnace might need to increase this range to three to 10 cycles.
Generally, it's useful to have your heating come on around half an hour before you get up in the morning. Then, have turn it off again around half an hour before you go to bed. If you're planning on being out of the house, you can turn the heating off while nobody's in.
Bump the temperature up 3-4 degrees above the room temperature so the heat will come on. Watch the thermostat for a minute or two and make sure “aux” or “emergency” heat doesn't come on yet. Check outside and make sure the condenser unit started up successfully and you don't hear any unusual noises.
One of the most common complaints among homeowners who possess a furnace is that their unit runs continuously. Unless you also have a heat pump (which can cause your unit to run frequently to maintain a set temperature during extremely cold weather), your furnace should cycle on and off at regular intervals.
Each heat cycle lasts around 18 days, for generally anywhere from 2 to 3 weeks. The frequency depends on your dog, but her estrus cycles should be consistent. If these are inconsistent, your vet can determine if your dog has irregular seasons. As your dog gets older, the frequency of her seasons may slow down.
Dirty Air Filters
So, the furnace is triggered to stop, then it cools down only to fire back up again. This short cycling continues to repeat until the furnace receives the airflow it needs. Dirty air filters are one of the most common reasons behind furnace short cycling.
Industry research shows some expected time frames for how long a furnace runs during a particular cycle. Running 10 to 15 minutes per cycle seems acceptable. So is running as long as 20 minutes. Even running every seven or eight minutes may not be a problem, as other factors could lead to more frequent cycling.
There are four common reasons why a furnace would short cycle; It has a dirty air filter inhibiting airflow to your blower motor, your thermostat is malfunctioning, you have poor insulation, or your furnace is oversized.
The system will turn off prematurely and then quickly turn back on in an attempt to reach the set temperature. The thermostat will incorrectly tell the unit that the set temperature was reached or vice versa.
During an average heating cycle, a furnace should operate for 10-15 minutes. If you're wondering how often furnaces cycle, the answer is: it depends. Furnaces in homes with average insulation might run two to three cycles per hour to heat the living space properly.
One of the most common causes of a furnace shutting off unexpectedly is low airflow. If your furnace keeps turning off, check for issues such as: Dirty Air Filters. A clogged filter restricts airflow, causing the furnace to overheat.
Short cycling is a common sign of a bad flame sensor. The sensor thinks that there isn't a flame, so it shuts off the gas as a safety mechanism. Except, there is a flame and without the gas to supply it, it dies. This is a frustrating problem, but an HVAC technician can fix it.
An average furnace will in fact turn off and on only a couple times in an hour. However, during these times the furnace should be lasting around 5 minutes or longer. If it isn't that cold outside it's easier for your furnace to get your home to the desired temperature vs an extremely cold day.
The most economical way to manage your central heating is to turn it on for 8 to 10 hours per day. Program thermostatic radiator valves to come on about half an hour before you wake up and switch off a half hour after you go to bed.
However, most heat pumps should complete about two to three cycles per hour, with about ten minutes of downtime between each cycle.