Typical AC Cooling Cycles An AC that works will typically perform two or three cycles an hour. On moderately hot days, your AC should typically only run for 10-15 minutes to cool your house thoroughly. This means it will often run for around 10 minutes before shutting off and then stay off for about 10 minutes.
Understanding how often your AC should turn on and off can help you maintain a comfortable and energy-efficient home. Ideally, your AC should cycle two to three times per hour during normal weather conditions.
If you have noticed that your air conditioner has been turning on and off as frequently as every 10 minutes, your system is most likely in need of repair due to “short-cycling.” Short-cycling is when a system turns on and off abruptly and often.
When things are working right, your central air conditioner should run for 15 to 20 minutes and then turn off for a few minutes. It will do this two or three times every hour. It may run longer when it's sweltering outside. And, much shorter cycles can mean there's a problem.
Poor Airflow
If something blocks the flow of air, your AC needs to go into overdrive to make up for it, which could result in it overheating. And when your AC overheats, it shuts off to give the system a chance to cool down. Once cool, it turns back on again, and the vicious cycle of short cycling continues.
When your AC turns on, it will usually need to run for anywhere from 10 to 20 minutes to cool your home completely. If the AC turns on and quickly shuts off again within a couple of minutes, there might be a major issue causing your unit to short cycle.
A bad thermostat can be detected when your AC or furnace is not turning on, your HVAC systems are not turning off, the thermostat not responding, your HVAC system is short-cycling, the room temperature not matching the temperature displayed on the thermostat, and the programmed setting resetting themselves.
Allowing your air conditioner to rest is an excellent way to extend its life and ensure it operates efficiently throughout the years. Air conditioners, like homeowners, require rest in order to recover and perform optimally.
Cooling a house from 90 degrees to 72 degrees typically takes about 2 to 4 hours, depending on various factors.
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.
Malfunctioning Thermostat
If the wiring between the AC and the thermostat is faulty, or if the thermostat is miscalibrated, your AC may begin to short cycle. Your thermostat may not properly register the temperature inside your home, forcing the AC to repeatedly start and stop in order to reach the desired temperature.
What is Short-Cycling? Short-cycling is when a furnace or boiler keeps turning on then off for very short durations. A “short duration” in this instance is generally defined as less than a minute up to a few minutes long. Some short-cycling heating systems will turn on and off after just a few seconds.
You do have to worry if your AC regularly shuts off in under 10 minutes, as this indicates it is short cycling. Another sign that your AC is short-cycling is if it frequently shuts off before the thermostat registers the correct temperature.
Is it OK to turn AC on and off frequently? Yes, it's okay to turn your AC on and off frequently. It can save you money on your energy bill, and your AC works best when it runs at full speed.
Here's the thing: It's normal for your AC to run continuously during hot summer months. You see, on extremely hot days—we're talkin' high 90s to 100s—your system needs to keep up with the incoming heat. To do that, it will run longer in order to maintain a constant, desired temperature in your home.
Ideally, a properly operating air conditioner should cycle for roughly 15 to 20 minutes, two to three times per hour. If the temperature inside your home is very high, is much higher than the temperature that your thermostat is set at, or the outside temperature is very high, the run time will increase.
Central AC Short Cycling
Homeowners spend between $75 and $600 to deal with short cycling issues in their central AC systems.
Should I turn my AC off if it is short cycling? No, this is not necessary unless the evaporator coils are frozen, in which case, turn off your air conditioner to let the coils thaw.
Depending on the system, an optimal time of 3 minutes is required before switching the system on. If the system is turned on without waiting for at least 3 minutes, the system can start with a pressure load. This pressure load prevents the system from cooling properly, which could affect the system in the long run.
Ideal Cycle Times for an Air Conditioner Unit
So, if the system shouldn't have long or short cycles, how long should an air conditioner run? Ideally, air conditioning systems should cycle for 15 to 20 minutes.
Your AC unit doesn't need to rest during the sweltering summer heat. Air conditioners are designed to operate continuously for extended periods, especially during summer when the heat is at its peak. In fact, shutting your AC unit off for extended periods could actually hurt your unit in the long run.
Replacing a Thermostat. You'll pay between $15 and $300 for the unit in addition to labor ($65 to $100 per hour) to replace an old thermostat with a new one.
Malfunctions affecting different system components can prevent the conditioner unit from shutting down as expected, such as a clogged air filter, a frozen evaporator coil, a faulty electrical relay switch, a dirty condenser coil, a constantly blowing fan, a bad thermostat, low refrigerant, and other HVAC system repair ...