How Long Should An Air Conditioner Run And Why?

logo by Editorial Staff | Updated on July 30th, 2022

15 minutes is the exact answer.

An air conditioner is a necessary in the summer. But are you aware that you must turn on and off the air conditioner after a certain period? Many individuals, no matter what, do not switch off the air conditioner. If you’re looking for the answer to how long your air conditioner should run in a cycle, you’ve come to the correct spot.

white and gray box fan

Is it safe to leave the air conditioner running all day?

While it is theoretically safe to leave your air conditioner running all day, it is rarely the wisest choice. Why? Because it wastes electricity, raises your energy prices, and hastens the demise of your air conditioner.

Should the air conditioner be left on all the time?

Some individuals prefer to keep their air conditioner on 24 hours a day, seven days a week. It’s easy to understand why. When it’s hot outdoors, you don’t want to be inside where it’s more hotter. Isn’t it true that running the air conditioner all the time is the best method to keep your house more comfortable?

While it is possible to keep your air conditioner running in principle, it is not a good idea in practice. For starters, by continually operating it, you dramatically reduce the lifespan of your AC unit.

Because it is using all of its parts to keep it going, those parts will wear out quicker, resulting in increased repair expenditures and perhaps the need for a new unit sooner than you’d want.

Furthermore, it wastes a lot of power when the machine is turned off. The more it runs, the more electricity it consumes. That means higher utility expenses for you, something you just despise. You’ll save a lot of money if you switch off the air conditioner.

The worst way to utilize air conditioning is to leave it on when you’re not at home. People do this because they don’t want to return home to a hot house, but a contemporary unit can chill your house down quickly. Make it a practice to adjust your thermostat up when you leave the house and back down when you return. This will stop it from running while you are not present to benefit from it.

Another time you don’t want your AC running is while you’re sleeping. If you raise your thermostat before going to bed, your house will still be chilly when you sleep, and you won’t experience the advantage of air conditioning because you’ll be in bed. This is one another technique to save energy and wear and tear on your unit.

Factors influencing how long your air conditioner operates

A variety of factors influence how long your air conditioner operates, including:

1. The Outside Temperature

The longer your air conditioner needs to operate to attain your target temperature, the hotter it gets.

This is especially true when humidity levels are high.

You shouldn’t be concerned if your air conditioner runs more frequently on really hot days. You don’t need to be concerned as long as you’re comfortable and cool air is pouring out of your vents.

2. The Temperature Setting on Your Thermostat

In the summer, the lower you set your thermostat, the longer your air conditioner will have to work to reach it.

While you may like it to be as chilly as possible, changing your thermostat by a few of degrees may reduce your air conditioners run time and save you some money on power.

3. Your Air Conditioner’s Size

The size of your air conditioner is the most important determinant in air conditioner run times.

An overly large air conditioner will reduce your run duration to roughly 10 minutes or less. This is referred to as short-cycling, and it occurs when your air conditioner cools your home too rapidly.

The amount of humidity in your home is also affected by short cycling. Although a large air conditioner would chill the air, it would not dehumidify your home. This suggests you’re still hot and sticky.

An insufficiently sized air conditioner will have the opposite effect. It is unable to effectively chill your home, therefore it continues to run. Anything more than 20 minutes with little to no temperature change indicates that your air conditioner may be too tiny.

4. The Condition of Your Air Conditioning

Air conditioners, like everything else, age.

When you take proper care of your air conditioner, it will continue to run effectively and potentially have a longer lifespan.

A neglected air conditioner, on the other hand, has the opposite effect. It will not chill your home as well, therefore it will have to run longer to attain the appropriate temperature.

This is harmful for both your air conditioner and your utility expenses. That is why we recommend a yearly tune-up to maintain your air conditioner in good working order.

5. The Dimensions of Your Residence

A larger house will take longer to cool, especially if the air conditioner unit is modest.

One approach to cut down on air conditioner run time is to strategically chill only the rooms you’re in. You don’t have to spend time cooling a guest room, for example. Instead, seal the dampers and doors and guide the airflow into your living room.

6. The Insulation Quality of Your Home

Your house need insulation all year. It is responsible for keeping the air in your house warm in the winter and cool in the summer.

A lack of insulation means that much of the air you pay to cool is really escaping out into the outer world. This implies that cooling your home will take significantly longer, and your air conditioner will operate longer to compensate for the loss.

How Long Does an Air Conditioner Have to Run?

DaysAir Conditioner Cycle
Hot Days15 mins
Mild Days10 mins

The hotter the day, the more you’ll need an air conditioner. Those who live in Africa or England during the summer months, when the temperature continues to rise, will need to use an air conditioner on a regular basis. It tries to chill your house and make your summers more bearable.

Keeping cool throughout the day is difficult, which is why you need an air conditioner. When the weather isn’t too hot, you can use your air conditioner a little less.

Whether it’s a hot or cool day, you should operate your air conditioner for no more than 15 minutes at a time. If there is leakage, ventilation, or your air conditioner is too small for the space, it will not perform properly. When it’s not too hot outside or it’s a nice day, a minute of air conditioning is all that’s needed.

If you turn on and off your air conditioner regularly, the interior parts of your air conditioner will be ripped. Your air conditioner’s lifespan will be reduced as a result of continuous maintenance and wear and tear. It is detrimental to the effective operation of your air conditioner.

Why does an air conditioner take so long to start?

Do you want to know what elements affect an air conditioner’s proper operation? Then you’ve come to the correct spot. On a warm day, you should operate your air conditioner for 15 to 20 minutes. However, this is entirely dependent on the ambient temperature.

The desire to turn on the air conditioner increases as the temperature rises. On hot, bright days, all you need to do is keep comfy and cool. Make sure the thermostat is set to a lower temperature. It will chill the space faster and allow you to save energy and time.

You should also think about the size and effectiveness of your air conditioner. The shorter the run duration, the larger the air conditioner. Also, the shorter time it takes to chill your space. However, if it is too tiny, it may take 20 minutes to chill the room without any change in temperature.

The longevity of your air conditioner is also determined by its condition. The next step is to determine the size of our room. It will take more time to cool down if the space is larger. However, it shortens the run time.

Examine your room for any leaks or dampers. Finally, you should inspect the quality of insulation offered by your air conditioner. Insulation is essential in the summer and winter. Inadequate insulation would result in the longest-running air conditioner.

Is it necessary to turn off my air conditioner when I leave the house?

In the height of summer, coming home to an ice blast is the finest part of the day. Is it, however, prudent to leave the air conditioning on for eight hours or more while we’re out and about? Simply said, it’s preferable to turn it off in terms of energy usage. Of course, it isn’t the entire tale. There are a few factors to consider.

  • The length of your trip influences whether you should leave the air conditioner on: Consider pulling a hefty shopping cart. It takes a lot of effort to get it moving, but once it’s moving, it doesn’t take much to keep it going. The same is true with air conditioning. Dropping the temperature ten degrees requires a lot more labor, a lot more electricity, and a lot more wear and tear than keeping the temperature ten degrees lower for the same period. If you’re only going to be gone for a few minutes, it may be better for your AC and your expenses to leave it on.
  • Don’t forget about your four-legged companions: Fido lacks sweat glands, and while animals have their own ways of staying cool, you shouldn’t allow your house turn into a sauna if dogs, cats, or other pets spend the day there. If you’re going to be gone for an extended period of time, you can absolutely put the AC down, but make sure it’s cold enough that the dog days of summer aren’t your dog’s worst days. You want your cool kitties to remain cool! In general, pets like temperatures no higher than 80 degrees Fahrenheit.
  • You may turn off the air conditioner at night: Although it’s apparent to turn down the AC, at least a bit, when you’re gone all day, the greatest time to let the air conditioner rest is at night. Not only is it colder outdoors (maybe cool enough to crack the windows! ), but we create a lot less heat while we sleep. Even beneath the covers, we require less assistance in staying cool than when we are rushing through our day.

When Should You Be Concerned

There are a few signs that something is wrong with your air conditioner.

  • Your air conditioner is always on. It is literally on all the time.
  • Your energy expenses are through the roof, yet you’re not changing how you use your air conditioner.
  • No matter how low you set your thermostat, the air temperature does not appear to change.
  • If you see any of these issues (especially the first), it’s time to look for a solution.

How Should the System Typically Operate?

When everything is working properly, determining how long the AC should run at a time becomes easy. If it’s an extremely hot day in Jacksonville, FL, the air conditioner should be on virtually the whole time. This will aid in keeping the temperature in the house at the temperature you have selected on the thermostat.

When the temperature outside is milder, the unit should not be left on all the time. It will operate in cycles. These cycles will normally last approximately 15 minutes and happen two to three times every hour. Again, this will assist you maintain the temperature you’ve set on the thermostat. When it’s much colder outside, it’ll need to run less, or not at all in some situations.


You no longer have to be concerned about the duration of your air conditioner’s operation. Air conditioners fluctuate, but we need to check to see whether it’s causing problems. Everyone desires a wonderful air conditioner. So all you have to do is improve it over time. Don’t waste your money on a small-sized air conditioner. Otherwise, additional repairs and power would be required.

An air conditioner should operate for around 15 minutes in order to maintain perfect conditions. If the temperature rises and continues to climb, you can increase the run time. However, try not to go beyond 20 minutes.


Editorial Staff

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