36000 BTU Window Air Conditioner | Room Size, Electricity, & Buying Guide

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Have you ever walked into a room on a hot summer afternoon only to find the temperature inside is not cool enough despite the air conditioner running continuously for half an hour? Blame it on a mismatch between the room size and air conditioner size. If the air conditioning unit is too small for a room, it will not be very effective in cooling it. Bigger spaces require large units, like a 36,000 BTU window air conditioner.

In this post, we will talk about the 36,000 BTU window air conditioner in greater depth, including the room size for which it is appropriate and its electricity requirements.

What Size Room will a 36000 BTU Unit Cool?

To find out the answer to this question, we need to understand two things:

  • how the cooling capacity of an AC is measured
  • factors that affect an AC’s cooling efficiency in addition to the size of the room in which it is installed

The cooling capacity of an AC is measured in ‘tons’ and is based on how many BTUs it can remove per hour. BTU stands for British Thermal Unit, which is a unit of heat. Therefore, the cooling capacity of an AC is actually based on the amount of heat it can remove in an hour.

One-tone air conditioners have a cooling capacity of 12,000 BTUs. This means a 36,000 BTU air conditioner has a cooling capacity of three tons — that is to say, it removes 36,000 BTUs per hour.

But how can we express this cooling capacity in terms of square feet?

For this, we can use the following general guideline: one-ton of AC is sufficient for 600 square feet of space under normal conditions. So, by extension, a 3-ton air conditioner (a 36,000 BTU unit) can adequately cool a room of up to 1,800 square feet.

But keep in mind that the cooling capacity of an AC is dependent on several factors besides the room size. These include:

  • The humidity and heat levels outside
  • Orientation of your home
  • Number and style of the windows
  • Insulation

If you live in a very hot and humid place, or if your house receives a lot of sunlight during summer, a 36,000 BTU window air conditioner may be able to adequately cool only 1,600 or even 1,500 square feet of space. Similarly, if you have too many or old-styled windows, or if your home is not properly insulated, the cooling capacity of your 36,000 BTU window ac may be less than optimal.

How big is a 36000 BTU Window Unit?

A 36,000 BTU air conditioner has a cooling capacity of 3 ton. Since the weight and dimensions vary by product, you should check the product details of the selected window air conditioning unit to find out its size and weight.

How Much electricity does a 36000 BTU Window Air conditioner Use?

A 36,000 BTU Window air conditioner uses roughly 3,600 watts.

What size breaker do I need for a 36000 BTU Air Conditioner?
The size of the circuit breaker depends on the unit you are installing. You can find out the right size for the breaker in the installation guide. If it says the breaker should be a maximum of 20A, you should opt for a 20A circuit breaker.

36000 BTU Window Unit Vs Mini Split Options

Whether you should install a 36,000 BTU window unit or a mini-split unit depends on your budget and personal preferences. We’ll walk you through the advantages and disadvantages of both to help you make an informed decision.

Upfront cost

A 36,000 BTU mini-split unit will cost you more upfront than a window AC — there’s no denying this fact. However, because mini split air conditioners are far more energy-efficient than their window counterparts, such a unit will save you money over the years.


Installing a 36,000 BTU window unit is much simpler than a mini-split unit. As a matter of fact, you may be able to install the former yourself. If you decide to go solo, make sure you take all necessary precautions to not hurt yourself. A mini-split AC unit is not something you can install on your own; you need professional help for that. Wondering how long does it take to install a mini-split air conditioning unit? Well, it may take several hours or even an entire day.

Maintenance Costs

Window air conditioning units are low maintenance since they have a single unit. Because a mini split AC unit has two components, it may require periodic maintenance to function at its optimal level.

Energy Efficiency

You may be able to cut down the cost of running air conditioner by as much as 40% by opting for a mini-split AC instead of a window unit.


Are you a light sleeper or someone who doesn’t like any kind of intrusive noise while working or listing to music or watching TV? If so, you may want to buy a mini-split air conditioning unit. That’s because a mini-split AC generally doesn’t make any noise. Window AC units, by contrast, tends to be noisy.


Durability is another strong point of mini-split air conditioning units. Compared to a 36,000 BTU window AC, a mini-split unit is likely to last considerably longer