What Size Generator to Run Air Conditioner?

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What Size Generator to Run Air ConditionerToday, having an air conditioner in your home or your RV is not a luxury anymore, it is almost a necessity. It will help you deal with the scorching heat. However, some times, the power goes off due to a blackout. Getting the ideal generator would help you keep it running and have a good night sleep.

What Size Generator to Run Air Conditioner?

The problems come in sizing the generator and brings the question, what size generator to run an air conditioner? The good news is, my article will lighten your burden by giving you ways you can size the generator ideal for your AC.

a) Know how are generators sized

The first step to knowing the ideal size of the generator you need to run your AC is understanding how generators are sized. The following aspects will help you get better.

1) Know the generator types available

Before you embark on what size to buy, you need to know the type of generators available. Mostly they fall under two main categories, portable, and standby/stationary. The portable model is more comfortable to move from one point to another, while the standby type is installed outdoors and mostly connected to the home power line.

Additionally, with stationary types, they have high power output than the movable type. When it comes to the portable models, you can have them wherever you want, even in your RV. They are also considered less noisy but require frequent maintenance than the standby models.

2) Understand How Generators Are Sized

Not every generator buyer understands how the models are sized. Different generators come in various physical and different capacity. Mostly, the sizing is on its size and not the physical size. Many confuse the term size with the physical dimensions, whereas it’s the electrical output. The measurements come in either watts (W) or Kilowatts (kW) which is 1000 watts.

The ratings come in two values, the starting/surge watts, and the running watts. The starting watts represent the maximum power the generator can provide is a few seconds to start the motor-driven appliances. The running watts, on the other hand, is the power the generator can give continuously for the rest of its run time.

b) Deciding on the ideal generator size

Now that you know how they are sized, it’s time you know what size you need before you can buy. The following factors will facilitate your sizing.

1) Identify your requirements

Depending on the AC model you have, start by noting its starting power and the running watts it requires. That will help you know your exact power requirement of the air conditioner. You also need to consider any other appliances you might want to run in case of a power blackout. The better part is, with the right generator, you can run anything in your household.

2) Calculate the wattage you need

Mostly the wattage requirement of an AC is written on a sticker behind the air conditioner. If hard to find, you can find it in the user manual. If you can still find it, you can ask the manufacturer for this information.

Another method of calculating wattage is using its capacity. The AC’s weight, measured in tons or BTU, will make it easier for you. Usually, this info is provided with the owner’s manual. Now, you need to multiply the weight by 3,500 to get the watts as 1 ton = 3500 watts.

However, that will give the surge/starting wattage, which is the total value of the power needed to start-up the appliance. But with this value, it’s quite easy to estimate the size of the generator you need to run the air conditioner. Mostly, air conditioners require more than 2000 watts to start up and run smoothly.

If there are other appliances that you will be connecting to the generator, you need to add their wattage too before you head to the market. Add everything, including the surge/starting wattage of all the motor-driven machines you will be running.

Once you get your values, let’s say 5000 watts then pick a generator with more than that to avoid fluxes. You need to give it some allowance and get to enjoy continuous and steady power supply to your household or RV.


What size generator to run air condition? I believe now it’s much easier for you to decide on the size generator ideal for running your AC. Right? Don’t allow you and your family stay in a room without a working air conditioner during a blackout or on your RV trip. Get the right size generator and enjoy the full benefits of your Air Conditioner.

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About the author

Sharif Miah

I am Sharif, 22, a student, currently doing the BBA program. Besides, I am an online Blogger.

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