Best Extension Cords for Air Conditioners (2021 Review)

You’ve installed a new window air conditioner, but the build in cord doesn’t quite reach. You need an extension!

If this sounds familiar, keep on reading to learn more about the best extension cords for your air conditioner!

In this proHVACinfo guide, you will learn the following:

  • What are extension cords for air conditioners? (What makes them different?)
  • What are the different types of extension cords for air conditioners? (Learn what matters)
  • How do extension cords for air conditioners work?
  • What do you look for in the best extension cords for air conditioners? (Crucial safety considerations)
  • And much more!
proHVACinfo | Extension Cords for Air Conditioners

Short on time? Check out our quick list of the best extension cords for air conditioners!

ImageProduct
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Powtech 12ft 14-Gauge Appliance Cord
  • Angled Plug
  • Heavy Duty Insulation
  • UL Listed
  • Angled Plug
  • Heavy Duty Insulation
  • UL Listed
View on Amazon
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Thonapa 10-Gauge Extension Cord
  • Thermoplastic jacket
  • Internal LED Lights
  • Weather-Resistant
  • Thermoplastic jacket
  • Internal LED Lights
  • Weather-Resistant
View on Amazon
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Qualihome Heavy Duty Air Conditioner Cord
  • Flush Wall Connection
  • ETL Listed
  • Sturdy Construction
  • Flush Wall Connection
  • ETL Listed
  • Sturdy Construction
View on Amazon
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Clear Power Heavy Duty Extension Cord
  • Locking Connector
  • Flame Retardant
  • Designed For High Draw Appliances
  • Locking Connector
  • Flame Retardant
  • Designed For High Draw Appliances
View on Amazon
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Iron Forge Tools 10ft Lighted Extension Cord
  • 3-Socket Outlet
  • 10-Gauge Cable
  • Lighted Connections
  • 3-Socket Outlet
  • 10-Gauge Cable
  • Lighted Connections
View on Amazon

What Are Extension Cords For Air Conditioners?

Put simply, an extension cord for an air conditioner is a heavy duty cable designed to handle the high power draw that is demanded from devices like window air conditioning units.

If you happen to look at the pre-installed power cord on your window air conditioner, you’ll undoubtedly notice that it’s significantly thicker than the cord on other devices you may own, for example a cell phone charger, or even a TV.

This is because they use thicker wire than standard cables, capable of handling a higher current safely.

With that in mind, an extension cord for an air conditioner is similar in principle to a standard extension cord.

It plugs into your appliance’s cable and extends its range, but with the critical difference being that it has a larger gauge wire, similar to the pre-installed cable on the air conditioner.

Using a standard extension cord will create a bottle neck effect, causing the extension to overheat and potentially start a fire.

What Are The Different Types Of Extension Cords For Air Conditioners?

When shopping for your air conditioner extension cord, be aware of these key differences.

Voltage, Amperage, and Wattage

As a basic physics refresher, wattage, usually referred to as a number of watts, is the unit in which an appliance is rated for how much electricity it uses to operate.

Amperage is a unit used to measure current.

Electrical current, just like a river, is how the electricity flows, but instead of water, it’s the flow of electrons that we’re measuring.

More amps mean a higher current.

Finally, voltage. Volts are the unit used to measure how much electrical force is being used to cause the electrons to flow.

So, a higher force used means a higher voltage.

As it relates to extension cords for air conditioners, you’ll find that they are rated on the three factors we just looked at.

They will be rated with a maximum safe amperage and wattage, typically by what’s known as the gauge (more on that below)

Be sure to check the information sticker on the back of your air conditioner for information about the power requirements, and never choose an extension cord that can’t handle those requirements.

Sometimes your air conditioner will say the amperage outright.

If not, it will indicate the wattage.  

In the US, a good rule of thumb is that every 600 watts equals 5 amps (since the US uses 120-volts).

Gauge

Extension cords for air conditioners are available in different gauges, differing in diameter depending on the duty load that they need to be able to handle.

The gauge rating is based upon American Wire Gauge, and is expressed as a number.

The larger the cable, the greater its ability to carry power over a longer distance – this is especially important as voltage drops over distance, and running equipment that uses a motor (like an air conditioner) with too little voltage can cause serious, and permanent damage.

Extension cords for air conditioners are usually a minimum of 14 gauge, which is considered medium duty.

The tricky thing with gauges is that lower-gauged extension cords can handle more amps (yes, you read that right!)

Check out our handy rule-of-thumb below:

  • 16-gauge cords can handle up to 10 amps for up to 100 feet
  • 14-gauge cords can handle 10 – 15 amps for up to 50 feet
  • 12-gauge cords can handle 10 – 15 amps from 50 – 100 feet

As a general principle, when running extension cords for higher-powered devices like AC units, you don’t want to use an extension cord any longer than necessary.

So don’t use a 50-foot extension cord when you only need to cover 10-feet.

For that reason, our recommendation below are generally on the shorter-end in terms of cord length (though several have shorter and longer alternatives).

proHVACinfo | DYK Extension Cords

Plug and Connector

Another area of difference you’ll find when looking for air conditioner extension cords is the plug and the connector.

The plug is the side referred to as the male end; this is where the prongs are.

The connector is the female end, where plugs are connected.

Extension cords are available in both grounded and non-grounded varieties. Grounded cables have 3 prongs and 3 slots.

One of the two flat prongs is the live, or hot conductor, and the other is the neutral.

The large round prong is the ground, or earth conductor.

If your air conditioner has 3-prongs on its built in cable, always use a 3-prong extension cord.

Other extension cords will have a 2-prong plug and connector.

You’ll note that on 2-prong cables, the two prongs and the slots on the connector are different widths. This is a safety feature to ensure that the live and neutral conductors always align with the circuit conductors of the socket they’re plugged into.

Remember, you can plug a 2-prong appliance into a 3-prong cord, but never plug a 3 prong appliance into a 2-prong cord!

Jacket Type

The jacket type refers to the exterior casing that houses the wires in the extension cord. Standardized letters indicate the cord has certain characteristics. They are:

  • S – Flexible cord; general use
  • W – Approved for outdoor use
  • J – “Junior”, 300-volt insulation (if there is no “J”, by default the cord is rated for 600v)
  • P – Parallel wire construction (like those used in air conditioner cords)
  • T – Jacket is made from vinyl thermoplastic
  • E – Jacket is made from thermoplastic elastomer rubber            
  • O – Oil-resistant

How Do Extension Cords For Air Conditioners Work?

The philosophy here is quite simple.

Plug your window air conditioner or standalone air conditioner into the extension cord, and plug the other end into a wall outlet.

This gives you extra range in the event that your air conditioner’s build in cable doesn’t reach, and if you buy an extension with multiple outlets, you’ll also gain extra connectors to plug in other devices and appliances.

Extension cords for air conditioners are available in a wide range of sizes, but remember what we said earlier – voltage drops over a longer distance, so if you only need to cover a 10 foot gap, don’t go for the 100 foot cable!

What Do You Look For In The Best Extension Cords For Air Conditioners?

As passive items, it can be tricky to tell the difference between good, and average extension cords.

So, if you’re trying to figure out what helps a cord to stand apart, take a look at these features.

Lighted Connections

Some of the best extension cords feature connections with lighting.

This handy feature helps to draw attention to the connection, which in turn helps to prevent trips and falls over the cable, and ultimately avoid accidental disconnections.

It also alerts you to the fact that there is power to the device, which, in the event of your air conditioner failing to power up, is a quick indicator that the fault is with the unit, and not the power source.

Ground Fault Circuit Interrupter

This is a device built into some extension cords that will automatically cut the power to the extension cord if a ground fault is detected.

Stopping the power in this way can prevent catastrophic damage to devices like air conditioners.

Locking Connector

A locking connector is a handy feature that prevents accidental disconnections.

They come in a couple of forms, sometimes as a box that closes over both the male and female ends, or a connector with a clamping lever.

Multiple Connectors

Having more than one connector will allow you to plug multiple appliances into the same extension cord.

Be careful to observe the maximum ratings of the cable vs the power draw of all of the appliances you plan to plug into it, though, and never exceed those maximum ratings to avoid risk of fire.

Our Reviews Of The Best Extension Cords For Air Conditioners

Final Thoughts On The Best Extension Cords For Air Conditioners

We’re glad that you’ve joined us for this proHVACinfo guide to extension cords for air conditioners.

Buying any old cable to extend the reach of your air conditioner can pose serious fire risks.

Taking the time to learn the power requirements of your air conditioner and research an appropriate extension cable is critical for safety.

Also, don’t take the power requirements too literally.

If your device draws 15 amps, don’t rely on a 15 amp extension cord, with continuous use it will still overheat and cause a fire risk.

Make sure you leave some headroom when it comes to power.

Our final words of wisdom – for safety reasons, you should only ever use extension cords as a temporary fix.

If you need a long term solution, have an electrician wire in a wall outlet within the reach of your air conditioner’s built in cord.

Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

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Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

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