Can You leave a Window Air Conditioner on 24/7?

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Window air conditioners are quite effective at cooling small spaces like studio apartments. While they are low maintenance, you can improve the functionality of your window AC unit by adhering to best practices. Selecting the right size for your room, cleaning the filter regularly, and installing it at the optimal location are a few ways to keep your unit working at its optimal level. Curiously, many people ask what is the best way to use a Window AC. Can it be left on all day? Will that impact its performance or lifespan? In this post, we will answer these questions and more.

So, can you leave a window Air conditioner on 24/7? Yes, you can leave a window Air Conditioner on 24/7. Experts say it is completely safe to run your AC throughout the day. The internal parts of an AC are designed to shoulder a continuous workload. Leaving it on continuously will not melt the internal parts, nor will they get too hot.

While your AC won’t get damaged if you leave it on 24/7, doing so can impact its ability to dehumidify your home, increase your energy costs, and hurt the environment.

How long can you safely leave a window AC running?

According to many experts, it is completely safe to leave your window AC on 24/7. The internal parts of your AC won’t get damaged if it runs all day long.

All the same, that’s not how most people use their AC. Instead, they invariably turn it off for some time after it has run for, say, two-three hours. Wondering why? We will explain.

Shared ahead are four main reasons why keeping your AC on 24/7 is not a good idea.

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  • It will require more energy

When you turn an AC on, its first goal is to achieve the desired comfort level. Once it reaches the temperature set by you, the thermostat tells it to tone down, which causes the air conditioner to trip in return. Things, however, start getting it costly here.

When an AC has to alternate between running at full throttle and tripping it uses far more energy than when running at top speed. That’s because the former involves a continuous start-stop cycle, whereas in the latter scenario there is hardly any disturbance to its performance. For this reason, if you don’t want your electricity bills to shoot northward, switch it off after a couple of hours or so.

  • Its ability to efficiently dehumidify your home will suffer

Apart from keeping your home cool, your air conditioner dehumidifies the indoor air by drawing in the moisture present in it. This not only improves the comfort levels but also eradicates allergens present in the indoor air and eliminates the bad smell that comes from damp indoor spaces. However, when an AC runs continuously, it isn’t able to optimally dehumidify the indoor air.

  • It is going to hurt the environment more

Everybody knows air conditioners are not good for the environment. Not only they consume a lot of energy, they also use cooling agents (HFCs and CFCs) that increase the holes in the ozone.

But does that mean we should do away with them completely? Practically speaking, that is not possible. However, what we can do is turn it off once the desired comfort level is achieved. The logic is simple. The more your AC runs, the more its carbon emissions will be. When a 1.5-ton air conditioner runs all day, it emits about 5344g of carbon. In contrast, the same AC emits 222g of carbon when it is kept on for 8 hours. You can help the environment by switching the AC off after every few hours.

  • It may reduce the AC’s lifespan

Just like any other electrical appliance, the AC is prone to wear and tear. The more you use it, the more vulnerable it is likely to get. Giving your AC rest can increase its lifespan.

Why is a ductless AC mini-split a good alternative to a window air conditioner?

Here are some compelling reasons why ductless AC mini splits are a good alternative to window ACs.

  • It is more energy efficient

Did you know that you can reduce the cost of running an air conditioner by up to 40% by using a mini-split AC instead of a window unit? This means your monthly energy bills will not surge a lot even if you keep your ductless AC mini-split on for longer periods of time.

  • It is quieter

A ductless AC mini-split is much quieter than a window AC. This can be a valuable feature for people who don’t like any sort of disruptive noise while sleeping, working or relaxing.

  • It can heat your home in winter

A window AC can only cool your home in summer; it can’t heat it when the temperature outside drops to zero. A ductless mini-split unit, however, is multi-functional. It can cool your home in the summer months and keep it warm during winter.


Running a window air conditioner all day long will not damage its parts, but it will surely increase your energy bills. Also, it will not be able to dehumidify your home as well as you like. On top of all this, a window air conditioner that runs 24/7 is harmful to the environment. For this reason, we recommend you turn off your unit after every few hours. You may also want to consider a ductless mini-split AC in place of a window one since the former is more energy-efficient and makes less noise. You can also use it to keep your home warm in winter.