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What Size AC for 1800 Sq Ft? (All You Need to Know)

When installing an air conditioning unit in your home, you’ll need to take into account the unit’s size and the square footage of the room.

By measuring the humidity level in the room, you can determine which 1800 sq ft unit is best for a given space. Let’s find the AC size for a room of 1800 square feet.

Ac size for 1800 sq ft:

A general rule of thumb is to provide 20 BTUs of cooling per square foot of space. It is therefore appropriate to install a 36000 BTU unit in a room that is 1800 square feet in size. According to the type and brand of air conditioner installed, this site may require a 3-ton unit.

Generally, the larger the AC unit, the more efficient it will be at cooling your room. If you have an 1800-square-foot room, an oversized air conditioner like a 3 tons unit will not only save you money on energy costs over time.

It can also reduce the frequency of repairs or replacements. Based on the assumption that the room is filled with air and that no objects are blocking the airflow, this calculation is performed.

It may be necessary to purchase a larger AC unit if you have hardwood floors or high ceilings. To get an accurate estimate of the size and type of AC unit needed for your home, you should consult an HVAC technician.

How do I calculate what size air conditioner I need?

To determine the air conditioner size needed to cool a space, measure its square footage first.

Next, determine how many BTUs are required to provide cooling for each square foot of the room based on this information. The final step is to choose a unit that provides at least this amount of cooling per watt.

Here is the formula you can use. BTU= (20*square foot).

In the case of an 1800-square-foot room, the calculation would be as follows.

= (20*square foot)


=36000 BTU

In addition to converting BTU to Tons, you can also convert BTU to Kilograms. To do this, you only have to divide the number of BTU by 12000. It is possible to use the formula as follows to calculate this value. Ton(s)= BTU/12000.

In the case of your room, for example, you will need a cooling system with 36000 BTUs. Here is the calculation that needs to be done.

= BTU/12000


=3 tons

Additionally, an AC unit with a higher SEER rating will be more efficient and therefore use fewer BTUs to provide the same level of cooling.

Despite this, higher SEER ratings also cost more, so consult an HVAC technician to make sure the AC unit you choose meets your needs.

What type of Air Conditioner is best for an 1800 sq ft space?

The best air conditioner for an 1800 square foot space is a window unit. Installing a window AC unit is quick and easy, and it does not take up much space.

The AC unit can also be run continuously when it’s hot outside because the windows are open. The following are some of the best air conditioners for 1800 square feet.

Window AC unit:

It is very easy to install a window AC unit for an 1800 square foot space because it does not take up much space and can be installed quickly and easily.

It is also important to keep in mind that window air conditioners can be quite noisy when they are operating, so if you have neighbors close by, make sure that the unit you choose has noise reducers or filters attached to it.

SEER 12 Cooling System with ESP:

Invest in a SEER 12 Cooling System with ESP if you’re looking for superior cooling performance in 1800 square feet.

The units that are used for this purpose are typically much more energy efficient than standard window air conditioners, and they can also be used to cool larger spaces as well.

Carrier XL window AC unit:

The Carrier XL window AC unit is another great option for 1800 sq ft. This type of air conditioning unit offers superior cooling performance and is usually quieter than other types of air conditioning units.

The majority of these models tend to be more affordable than those that come with higher SEER ratings, so if the price is a major consideration for you, this might be the best option for you.

Room AC Unit:

It might be best to install a room air conditioner if you do not want to install a window air conditioner.

Despite being more expensive and taking up more space, these units can still be installed quickly and easily. To reduce the noise level of running AC units, larger ones often come with filters and noise reducers.

Things to consider before choosing an AC size for an 1800 sq ft home:

For those who are wondering which AC size to choose for their 1800 sq ft home, there are several things to consider:

Room size:

Generally, the larger the room, the more air conditioning you’ll need.

Generally, a window air conditioner will be able to cool an 1800 square foot space comfortably, but if your home is larger than that, you may want to consider a bigger model or a higher SEER air conditioner.

Number of people and pets in the home:

The AC unit will take longer to cool down your home if there are a lot of people or pets in it, and it will also make more noise. There are times when a room air conditioner may be the best option for you in cases such as these.

Location of the home:

Choosing an air conditioner with a higher SEER rating will help you ensure that your room remains cooler or warmer than you’d expect it to be if you live in an area that is especially hot or cold.

Seasonal Heat Gain:

In climates where temperatures change significantly throughout the year, it’s important to consider that when making decisions.

In hotter months, areas near windows are more likely to experience increased heat gain, so choose an air conditioner with a higher SEER rating if this is an issue.

Room type:

Some rooms are more sensitive to heat than others. A unit with a specific cooling or heating capacity may be most suitable if you have a room that tends to stay very hot or cold for long periods.

As an example, a central air conditioner is usually the best option when it comes to cooling a bedroom because bedrooms tend to stay cooler than other parts of the house during the summer. 

Air Conditioner Cost for 1800 sq ft:

The average cost of an air conditioner for a space of 1800 square feet is around $2500 to $5,000. Several factors determine the cost of the air conditioner, such as the type, features, and location of the air conditioner.

AC price:

For a room that is 1800 square feet, you will need a minimum of a 3-ton air conditioner. A 3 tons standard air conditioner will cost you between $2000 and $4500, depending on the brand.

In addition, you need to have a minimum budget of $500 for the installation process. You can, however, find it cheaper if you compare several quotes from different companies to get a better deal.

Running cost:

The cost of running an air conditioner in an 1800 sq ft room will differ depending on the model and make but is typical $0.48 per hour for a 36000 BTU AC.

There will be a cost each year of approximately $4200 because the AC unit runs 24 hours a day, 365 days a year. 

When calculating your costs, be sure to include electricity costs.

As a rule of thumb, it will be a good idea for you to have a fixed-rate plan with your electricity company to compensate for any increases that may occur due to surges in demand during hot weather periods.

Final thoughts

A room of 1800 square feet requires 36000 BTUs or 3 tons of air conditioning. If you have this size room, you should also have a Window AC unit or a SEER 12 Cooling System with ESP. Consider these factors before choosing any Ac: Room size, Number of people and pets in the home, and Location.