How long can you use a portable air conditioner?

Most of us don’t think twice about running air conditioning systems for long periods of time. But there’s something about leaving a portable air conditioner plugged into a wall outlet 24/7 that seems dangerous. You wouldn’t leave your oven running overnight, would you?

How long can you use a portable air conditioner?

You can use a portable air conditioner for as long as you want provided the unit is plugged into a safe power source. Portable air conditioners are designed to run 24/7 on hot summer days. 

In fact, running a portable air continuously is better from a maintenance perspective than turning it off and on every day. The shut-down and start-up process places more strain on your portable ACs components and increases the need for maintenance over time.

Of course, optimum maintenance isn’t the only consideration when deciding how long to use your portable air conditioner. You may live in a relatively small space given your air conditioner’s cooling output. 

Running a portable air conditioner would waste a lot of energy if your home already reaches a comfortable temperature after just a few hours of use.

Most portable air conditioners use 2.9 kWh – 4.1 kWh of electricity per hour. That translates to $0.66 – $0.94 per hour to run most portable air conditioners. 

If you’re running your portable air conditioner for 6 hours a day, then increasing your usage to 24 hours would cost you an additional $11.88 a day and $356.40 a month.

Our recommendation is only to use a portable air conditioner for 24 hours a day if you need that level of cooling power to keep your home at a comfortable temperature. Otherwise, the cost of running a portable AC continuously outweighs any maintenance benefits.

Some portable AC units come with an automatic shutoff feature. These units sense the temperature in the room and will turn off once they register the desired temperature.

What is the most efficient amount of time to use a portable air conditioner?

The most efficient amount of time to use a portable air conditioner is to run your unit for 4 – 6 hours in the morning before the day’s temperatures hit their hottest. 

That might seem like a counterintuitive recommendation. Most people would assume that you should run your portable air conditioner during the hottest hours of the day to save yourself from the worst of the heat.

The problem with turning your portable AC on once you feel uncomfortable is that your home’s interior temperature has already increased by that point. So your portable air conditioner has to do additional work in order to get it down to the right temperature.

Take a boiling pot of water as an example. The pot will take ages to boil if you pour cold water into it and put it over the hob. That’s because your hob has to transfer a lot of energy into the pot just to bring it up to the right temperature. 

Alternatively, if you pour boiling water from the kettle into your pan and then put it over the hob, the water starts boiling almost immediately. It takes a lot less energy to keep water (or your indoor air) at the right temperature than it does to change its temperature.

Your home will start at a relatively comfortable temperature early in the morning because it’s been exposed to cooler outdoor temperatures at night. As outdoor temperatures rise, your home’s indoor air will slowly start to absorb some of the heat from the outdoor air, no matter how good your insulation.

The best strategy is to use your portable air conditioner to offset this increase in temperature throughout the morning, keeping your home at a stable, comfortable temperature throughout the day.

Then, turn your portable air conditioner off during the hottest part of the day. Your home’s indoor temperature will still be cool and will only rise a little during the few hours when the outdoor temperatures are the highest. 

This is like putting a cold pot of water over the hob. The water will heat up a little bit but there’s such a difference between the temperature of the water and the energy produced by the hob that it takes a very long time.

Another consideration is that running your portable air conditioner during the hottest part of the day actually hinders its performance. A portable air conditioner needs to get rid of excess heat by pumping it out the window via an exhaust tube. 

This process is a lot less efficient if the outdoor temperature is higher. So you’ll actually get a lot more cooling power by running your air conditioner during the cooler parts of the day.

What is the lifespan of a portable air conditioner?

The life span of a portable air conditioner is 10 years. Portable air conditioners don’t last as long as other types of air conditioners because they are more often moved and pick up more damage.

10 years might not sound like a ton of time compared to the 15 – 20 year lifespan of other air conditioning systems. However, the lower upfront investment for a portable air conditioner justifies a shorter lifespan in our opinion.

You should expect to pay $400 – $700 for a portable air conditioner while a split AC or in-wall AC will cost you thousands of dollars. 

The main reason portable air conditioners break faster than other units is because they are designed to be moved from location to location. That means they are much more likely to pick up damage to their core components as they are bumped or installed incorrectly.

You can extend the lifespan of your portable air conditioner by limiting the amount of movement from location to location and being very careful when transporting the device. 

The make and model of portable air conditioner will also have a big impact on how long your portable AC will last. More expensive and more durable units will generally be more resistant to damage than cheaper alternatives.

A lot of units even come with multi-year warranties. The length of a manufacturer’s warranty is a better indication than price of the durability of a portable AC. If the manufacturer is willing to bet their product will last for at least a few years, so should you.