can you use an extension cord with a portable air conditioner

Can you use an Extension Cord with a Portable Air Conditioner?

Can you use an extension cord for a portable air conditioner? In this article, we’re going to explore the art of using extension cords with portable ACs and how to stay safe at all times!

Extension cords are one of the weak points when using portable ACs. Generally, portable ACs are very safe. However, they need lots of power.

And when a weak extension cord has to handle too much power, it can melt or even catch fire.

That’s why you need the right-sized extension cord for your portable air conditioner.

Quick answer: Yes, you can use an extension cord for a portable air conditioner. But make sure your extension cord supports the amperage of your portable AC. Otherwise, you risk a fire. Most portable AC units draw around 12 Amps of current. Your extension cord must be able to handle this.

Are you not sure if your extension cord at home can handle it? Keep reading. I will recommend to you a few heavy-duty extension cords you can buy that can handle high amounts of current.

Before we dive too deep into what makes an extension cord safe to use for portable ACs, in this section I’ll link you my personal favorite extension cords.

For portable air conditioners, I recommend this POWTECH Heavy Duty extension cord (click here to view it on amazon). It supports up to 15 Amps and 1875 Watts of power, which makes it a perfect fit for high-current home appliances such as portable air conditioners. You can also use it with electric space heaters and other devices.

Please note that this extension cord has a length of 20 feet. 

If you need any longer than that, I recommend you get this Clear Power high-quality 100 feet extension cord (click here to view it on amazon).

It’s a lot longer than the 20 feet extension cord. But it’s worth it. I guarantee you that you need such a long extension cord at least once every 5-10 years and each time you will regret not having one.

For such lengths I would not save money as long cords produce more heat and low-quality products will increase your energy bill as the electric resistance is too high

Prerequisites for Extension Cords for Portal ACs

Now that you know which extension cords you can use with a portable air conditioner, we can have a deeper look into what makes an extension cord safe to use.

First and foremost: Not all extension cords are the same. Extension cords vary in gauge (thickness of the wire) and materials used. Different types of extension cords are best suited for different applications.

For usage with a portable AC, an extension cord must be rated to handle at least the amount of current the portable AC uses. 

Usually, it is best to leave some room for tolerance. If you have an appliance that uses 13 Amps of current, you should not settle for a 13A-rated extension cord. You don’t want to operate the extension cord at its very limit all the time. A slight power spike can overload the extension cord wires and cause a meltdown.

Always use an extension cord that can handle your appliance for sure. For 5A devices, use a 7A extension cord. For 10A devices, use a 12A extension cord. And so on.

The underlying philosophy is going the safe route because risks and benefits aren’t balanced. When you use a cheap extension cord, the biggest benefit is that you save a few bucks. But the risk is that your house burns down.

Risks and benefits are not balanced. Get a solid high-gauge extension cord, such as the ones I recommended earlier.

How much current do Portable ACs use?

Portable ACs need different amounts of power. This depends on how much “cooling power” a portable air conditioner provides and also on how efficient it is.

There are portable ACs that use anywhere from 1000W up to 1500W.

On average, a portable AC uses 11.6 Amps, which usually corresponds to 1300W of power.

The low-power portable ACs draw 9.5A of current, while high-power ACs draw up to 14A of current.

However, these numbers are not representative at all times. A portable AC can draw 9A at one moment and 14A at the next. This depends on how the thermostat in the portable AC is working.

Also, even though some portable ACs are rated for lower currents, they can surpass these limits. If a portable AC has no sufficient safety mechanisms built-in, nothing prevents it from drawing more current than what is listed in the technical user manual.

Many homeowners experience this phenomenon. One writes

“This unit is supposed to draw a maximum of 9.5 amps, and it would be a little below that when it was first turned on, but then it would gradually pull more and more, getting up into the 13-14 amp range.”

A customer rating a popular portable AC online

Because of these varying currents, I highly suggest you to be cautious when choosing the right extension cord.

Theoretically and according to the user manual of the aircon, you could grab cheaper 13A extension cords as they fit the current ratings.

I would, instead, suggest the following:

“Always use an extension cord rated at 15A or higher for portable air conditioners.”

Additional safety tips for using an extension cord with a Portable AC

When using an extension cord with a portable AC, you have to always have safety in mind. It is not enough to just buy a proper gauge extension cord that can handle the required amount of current.

Safety incidents can happen even with very good extension cords. Although they happen very infrequently as compared to when you use cheap extension cords, you should still consider the following safety tips.

Unroll the extension cord so heat does not build up

Portable ACs draw a lot of current. Depending on the extension cord you use, more or less heat builds up in the wire, because of the current flowing through it.

The higher gauge your extension cord is (high gauge = thick cable), the cooler your extension cord stays. The reason is that the current has more room to move freely. In technical terms, you can say that high gauge extension cords have less resistance per length.

When you keep the extension cord rolled up while you power a portable AC, it becomes more likely to overheat. Therefore, just make sure that your extension cord is not bundled up tightly, but it sits loosely on the ground.

Ideally, you should leave your extension cord loose while still being straightened out.

Having a proper-length extension cord for your specific use case helps.

Properly connect extension cord with the wall outlet

Make sure you connect your extension cord firmly with the portable air conditioner as well as with the wall outlet. A tight connection is important for safety as it reduces resistance.

When your extension cord is only loosely connected to the wall outlet or the portable AC, the electric current has to surpass a bigger resistance. The current is forced through the few “touching points” of the extension cord and wall outlet.

In loose connections, heat builds up because a lot of energy passes through a tight contact area.

Here, it doesn’t even matter if you have a cheap or an expensive extension cord. When the connection of the extension cord to the appliance or to the wall outlet is weak, heat always builds up.

Even expensive high-quality extension cords can cause a meltdown or even a fire.

Choose the right length

Your extension cord should be about the length that you need to connect the wall outlet and portable AC. It should not be much longer.

The longer the cord the greater the resistance it has. This causes a greater heat up in the cable as well as increased power usage.

The increased power usage stems from the fact that portable ACs (or any electric appliances in general) always try to draw a fixed amount of power. If the current faces a bigger resistance because of a longer extension cord, energy is lost in the extension cord. The portable AC then draws more power from the wall outlet to make up for the lost part.

This means: longer cables heat up more, produce more waste heat, and increase your energy bill.

Can you use a regular extension cord with a portable air conditioner?

Not always, but sometimes a regular extension cord you already have at home is suitable for your portable AC as well. It all depends on the quality of the extension cord and its power and current limitations.

You have to ensure that your extension cord is rated at a higher level of Amps than what your portable air conditioner requires. You can oftentimes find the Amperage rating of your extension cord printed on the cable itself.

I would advise staying away from extension cords rated below 13A, because, as we saw earlier, portable air conditioners can unexpectedly spike in current.

Lots of extension cords are rated for 8A or 12A devices. These extension cords are cheap to get and are more common than the high-gauge ones. They might even work for some time.

But eventually, these extension cords will fail and cause some kind of problem of medium to high severity, such as a blown fuse, a meltdown, or a fire in the worst case.

The problem with these “regular” low current extension cords is that they are too thin to handle large amounts of electric current. Their resistance is too high and causes heat to build up.

The low-quality materials used in producing these cheap extension cords will fail quickly when you use them with portable air conditioners.

Extra safe extension cords

If you are a risk-averse person, then going for a good quality extension cord is already a good choice. But if you want to be absolutely sure that you minimize the chance of an accident, you can get an even higher gauge extension cord.

30A extension cords for high current outdoor appliances could be your choice in this case. Usually, you would use these extension cords to connect high current appliances from distant power outlets. The resistance of these high gauge wires is small, which improves the energy efficiency of your portable air conditioner.

One example is this 30A extension cord (click here to view it on amazon).

Such an extension cord is not really necessary. But when you want to go the safe route or your portable AC is an industrial type and therefore uses more than 1500W, you should go for it.

About the Author

Daniel Hirsch

Daniel is an electrical engineer, blogger, and author. He studied electrical engineering and information technology and decided to blog about heaters after working in the temperature sensing industry.