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Can You Plug an Air Conditioner into an Extension Cord?

Looking for a cost-effective way to extend your AC’s reach? Extending an extension cord is a great way to power devices that do not have their own power outlets. But does that mean you have to use an extension cord for your air conditioner? Let’s take a look at that.

Plugging an air conditioner into an extension cord

Air conditioners should not be plugged into extensions. Normal electrical outlets are capable of handling the power requirements of air conditioners. Due to the high-power draw of an air conditioner, using an extension cord can damage an outlet. It is only permitted for temporary use.

Extension cords are not designed to power air conditioners. Plugging an air conditioner into an extension cord results in too much voltage and current for the wire gauge, potentially causing an electrical shock or fire. 

An extension cord provides an extra-long reach and allows you to plug in devices that might be difficult or impossible to reach with a regular cord. Due to the possibility of overloading and damaging air conditioners, extension cords weren’t originally designed for them. 

Be sure to use a surge protector if you are plugging your air conditioner into an extension cord.

Portable air conditioner:

Extension cords can be used with portable air conditioners. Portable air conditioners are designed to be carried around. If you need to plug your air conditioner into a difficult or impossible-to-reach outlet, you can use an extension cord.

The outlet must, however, be properly wired and rated for use with a portable air conditioner. Check the extension cord for a ground fault circuit interrupter (GFCI) to help prevent electrical shock to you and your appliances.

Window air conditioner:

An extension cord cannot be used with window air conditioners. A window air conditioner sits on your window sill, and it plugs into the outlet below it. 

An extension cord would not reach into the window far enough to connect to an air conditioner, causing damage. Moreover, an extension cord could tangle around the window air conditioner, resulting in a malfunction.

Is it safe to use an extension cord with an air conditioner?

The use of an extension cord with an air conditioner is not recommended. It was not originally intended for extension cords to be used with air conditioners. Overloading and damaging an air conditioner can be caused by extension cords. 

In addition, an extension cord could tangle around the air conditioner, causing it to malfunction or even tip over.

In general, an air conditioner is powered by electricity from a wall outlet. Using an extension cord to power an air conditioner is essentially using electricity that isn’t designed for this purpose. There is a risk that this can damage the AC unit and even result in a fire. 

Nonetheless, if you must use an extension cord with an air conditioner, make sure to buy one that is specifically designed for this purpose and use a GFCI plug.

How to use an extension cord for an air conditioner?

Extension cords are not recommended when it comes to air conditioners, but you can use them together to solve your problem. It is important to follow these steps when you are using an extension cord with an air conditioner:

The first thing you should do is purchase an extension cord that is designed specifically for large electronic devices. Plug the extension cord into an appropriate outlet and the air conditioner into the extension cord. 

As a third step, make sure that you have turned off both your electrical grid and your breaker. Before unplugging any appliance, make sure that all electricity has been shut off by securing the cords with a wire nut or sturdy screw and waiting 30 minutes before doing so

Moreover, you should always plug an air conditioner into an electrical outlet with a GFCI safety protection that you know is reliable and has a reliable outlet. Therefore, by doing so, you will be able to avoid any potential problems or damage to your air conditioner in the future. 

For safety reasons, you will need to ensure that your extension cord is GFCI-protected if you use one so that any future safety hazards can be avoided should you have to use one.

What happens when you plug an air conditioner into an extension cord?

By plugging an air conditioner into an extension cord, you are essentially trying to power it with electricity that is not meant for this purpose. Consequently, the AC unit may be damaged, and a fire may even result. 

Plugging an air conditioner into an extension cord can lead to some of these situations.

Limit the air conditioner’s ability:

When you use an extension cord to power your air conditioner, you will essentially be limiting its ability to provide you with the amount of air conditioning that it is capable of.

Damage to the AC unit:

Air conditioners put excessive strain on their electrical systems if they are plugged into extension cords. In this case, the AC unit may become damaged and it might even fail completely as a result. 

Aside from that, if this type of strain continues for a long time, it might actually damage the wiring inside of the AC unit itself if it is chronic over time.

Lose power:

Using an extension cord to plug in an air conditioner can result in your entire home losing power. In particular, if you use other appliances that rely on electricity, this can cause major problems.

Causes fire:

Putting an air conditioner on an extension cord can lead to a fire. An extension cord can act as an electrical conduit, connecting the AC unit to an adjacent object. A fire could easily start in this area if there is any overheating or faulty wiring.

Inability to cool:

Using an extension cord may not be sufficient to cool your home adequately if you have an air conditioner. Since the extension cord can only supply a certain amount of power, it won’t be able to provide more. It could be difficult to cool a large space.

Safety hazard:

Using an extension cord to plug in an air conditioner is dangerous. A dangerous current can be generated if the extension cord fails, which can send a dangerous current into the house. There is a very good chance that this could cause electrical shock or even electrocution in some cases.

What gauge extension cord do I need for an air conditioner? How to measure?

For temporary use, you can use 10-gauge cords for air conditioners. To measure an air conditioner extension cord, you will need an electrician’s tape measure. Multiply the power your AC unit uses by the amps it uses to determine the size of your extension cord. 

The following steps will help you measure:

The voltage of your country:

Your country uses 120V as its voltage. The air conditioner should be plugged into extension cords with voltages that correspond to your country of residence. Plugs from one country can be used on another country’s extension cord and vice versa.

Determine the watt of the Ac:

The next step is to determine the wattage of your air conditioner. Plug an electric meter into an outlet near your air conditioner and wait for it to stabilize. Approximately 80% of the AC’s power should be drawn after a few minutes. 

For an actual wattage rating in Watts, multiply the reading by 1.3 or 1.5, depending on the type and model of your air conditioner:

Find the Amps:

Following the formula below will help you find the amps you need:

Amps = Watts / Volts

Taking an air conditioner, for example, it uses 120V power and requires 1.5 watts to operate. The amps will therefore be 120 x 1.5 = 180 amps. Consequently, you would plug the extension cord into an extension cord with an amperage of 150A and then plug it into the extension cord.

Use a gauge chart:

To determine what gauge is appropriate for you, please refer to this gauge chart


Find the extension cord:

After finding the gauge, you should find an extension cord that matches the recommendation based on the gauge. You will need to plug the extension cord into an extension cord with an American plug if you are in the United States. 

You will need to plug in an extension cord with a European plug if you are in Europe.

Final Thoughts

In brief, air conditioners should not be plugged into extension cords. The extension cord was not designed to be used for air conditioning and caused a fire. You can only use an extension cord when you are using a portable air conditioner. Ensure that the extension cord is at least 10 gauge.