Air conditioners are what keep you and your house cool during the scorching summer heat. Mounting an air conditioner, however, is not a simple task. So, if you just got an AC and the wall socket is too far away, what do you do? Can you plug an AC into an extension cord?

You should not connect a window air conditioner to an extension cord. Air conditioners tend to draw a lot of power. Typical extension cords will not be able to deliver this much power and can cause dangerous electrical fires. Not only that, but the reduced voltage may also harm your AC.

Extension cords can be used for small portable ACs. But there might still be risks. For window AC, it is a complete no-no because of the electrical and power limitations. Let’s dive into all of this in more detail.

Can you plug an AC into an extension cord?

This question is not even the right question to ask. Instead, think about whether or not to plug the AC into an extension cord. Technically, anything with a plug can be plugged into an extension. But whether it is safe and will work is what you should think about.

The short answer to this is a big fat no! You should never plug an AC into an extension cord. They are just not compatible, and it can be very dangerous to do so. For proper installation, air conditioners should always be plugged into a permanent and grounded socket.

Take a look at the cord of any AC unit. They are usually very short. That does not mean you can plug them into an extension cord if the socket is out of reach. This is because ACs require a lot of power.

And typical extension cords are just not built to deliver that much consistent power. A typical AC can pull about 1118 watts. That is much higher than what a typical extension cord is rated for which means that if you plug your AC into an extension that is unable to handle the amount of power drawn, it can cause a lot of issues.

What kind of problems, you ask? Well, we are talking about serious fires and overheating. None of which are things you want in the house. That is why plugging an AC into a grounded house socket is the only way to go. Apart from this, there are a couple of major problems with plugging an AC into an extension cord.

Lack of a circuit breaker

Air conditioners are one of the most power-hungry appliances in your house. That is why it is an absolute must to have a separate circuit breaker. This is to protect your house from electrical fires. Electrical fires can be dangerous, hard to put out, and just overall a nasty thing to deal with.

Most extension cords lack built-in circuit breakers or are not powerful enough to handle the power draw of an AC. Not even the smaller ones.

It reduces the voltage

Long and thin cords have high electrical resistance. These two things can cause the voltage to drop. That means your AC could get damaged. Components in the AC like the motor are very susceptible to these things.

AC compressors also need a constant level of torque to operate at normal levels. When you plug it into an extension cord, you will essentially reduce the torque. Reducing the voltage will also reduce the torque. This can cause the motor to stall. Again, a big no-no.

What if you buy an extension cord that works?

This is where things get a little tricky. You can actually find cords that have higher ratings in terms of voltage. You can find extension cords that are the right size as well. But you need to calculate the amperage and the power draw of your unit. Then you will need to buy an extension cord that matches this spec.

The power draw of your AC unit will be listed in the manual or on the chassis itself. ACs will generally draw somewhere between 900 watts and up to 1500 watts. First, check the watts your AC needs.

Then you need to check the volts. There will be either of two. Either it will be 120V or 240V. All that is left to do is divide the wattage by the volts. You will find the right ampere extension cord you need. The same goes for power.

You can use this method to check how much current will go through your AC, which will help you determine the right power for your cord as well. When selecting an extension cord, you will need to select one that is at least twice the ampere of your AC.

All that being said, I cannot stress this enough. Getting an extension cord is okay for small portable ACs. A window AC always needs to be plugged into a permanently grounded socket. You have heard me repeat this a couple of times by now. That is because it is that important.

Just to drive the point further home, there are a couple of scenarios in which you should not use an extension cord, regardless of the power limit:

  • If the distance is too long
  • If it does not have good insulation and protection
  • Never use an extension cord used for TVs and computers for your portable AC
  • Don’t place extension cords where there is heavy foot traffic inside your house
  • Never put the extension cord below any coverings or carpets

Final thoughts

Safety is more important than convenience. By now you should know the answer to: can you plug an AC into an extension cord? Just to reiterate, the answer is no!  If you do not have any way to use a window AC with a wall outlet, you can try using a small portable AC.

If you’re in an RV and asking the same question, you really need to consider buying a surge protector: Do I Actually Need a Surge Protector for My RV?

Installing an AC should be done by a professional in the first place. If the place you want to place an AC does not have a wall socket, you can talk with your electrician to have it installed. It may cost you some money, but it is worth it. It is safer and also better in the long run for your safety and the AC.