Type to search

What Size AC Unit Do You Need for 2,400 Square Feet?


One of the important preparations that you need to consider when buying an air conditioner is its relative size to a specific place. Being able to buy the right size AC unit for your desired cooling area will save you a lot of time and money.

Additionally, having the correct aircon size for your room contributes to its overall efficiency. But how do you measure the right size AC unit for your home? And how big should your air conditioner be for a 2,400 square unit place?

How Do You Calculate the Cooling Power for your Right Size AC Unit?

size AC unit

The cooling capacity of an air conditioner is expressed in either kilojoules/hour (kJ/hr) or British Thermal Units (BTU). This gauges how much heat your air conditioner can remove from the air in an hour of operation. You should use this value in your calculations since the cooling capacity of an air conditioner is typically expressed in the Philippines in terms of kJ/hr or BTU.

The capacity of an air conditioner can also be expressed in horsepower (HP) in addition to kJ/hr and BTU. It’s what you mostly see on labels of air conditioners in the market because manufacturers describe how much power the motor has to run the unit. However, HP it does not tell you about your air conditioner’s cooling ability.

The capacity of cooling systems on various models with the same horsepower rating may vary. Therefore, when determining the capacity of your air conditioner, it is much more accurate to measure models by kJ/hr and BTU rather than by horsepower rating.

Take note that for every 1.0 HP aircon it’s equivalent to 9,495 kJ/hr or 9,000 BTU. This can roughly cover a room with a size of 300-500 square feet. You can start by multiplying the room’s length by its width to determine the size of the air conditioner you’ll need for the space. To obtain adequate cooling for the room in a variety of weather conditions, multiply it by 500.

As a rule of thumb, we also refer to the capacity of an aircon to remove the heat inside the room as AC tonnage. It’s a much more accurate way to determine the right size AC unit for your room.

Why and How Do You Calculate the Right Size AC Unit for Your Room?

Now that you know how much cooling power you need to consider for your aircon, it’s time to determine the right size AC unit for your room. This can be done in more ways than one but calculating the AC tonnage is a much-preferred method. The reason is that the AC tonnage reflects the air conditioner’s cooling capacity.

It’s critical to correctly size your system because tonnage describes the cooling capacity of your air conditioner. The mid-summer temperatures won’t be able to be maintained by a unit that is too small. A large HVAC system may operate more frequently than necessary, causing unneeded maintenance, uncomfortable damp air, and higher electrical costs.

How Do You Calculate AC Tonnage?

As previously mentioned, AC tonnage refers to the right size AC unit per its cooling capacity. It’s measured in tons, and the greater it is, the more area, in square feet, it can cool. As a result, when someone inquiries about the “size” of the AC unit you need, they are requesting the number of tons, not the unit’s actual dimensions.

To determine the tonnage of your unit, just divide the BTUs by 12,000 instead. We use BTU in this calculation because it’s much easier to use than kJ/hr since it’s divisible by 12. For example, if your unit has a cooling capacity of 36,000 BTU then it’s equivalent to 3 tons. This is an important note to keep in mind because most manufacturers only display the cooling capacity on their brand model.

Additionally, below is an AC tonnage table you can refer to determine the right size AC unit for your home.

Room Area (sq. ft.)Cooling capacity (BTU)Tonnage (ton)

Following the table above, if your room is estimated to be around 2,400 square feet, then you will need an aircon with a cooling capacity of 48,000 BTU, and the right size AC unit is 4 tons.

Additional Tips in Choosing the Right Size AC Unit

While it’s of tantamount importance to consider the room size when buying an air conditioner, there are also other things you need to assess so that your AC can run more efficiently.

The number of windows in your house or building, the amount of shade or sunlight it receives, the need for ductwork, and the number of occupants should all be taken into account. These notes can affect the overall performance of the air conditioner, especially on its monthly maintenance.

You would also need to consider your geographic location, take note of the typical weather patterns, and check the age of the insulation surrounding your home or the area you want to cool.

Final Thoughts

size AC unit

It’s nice to know that air conditioners are modeled to accommodate our every need despite the varying room area. While it’s commonplace to think that a bigger area needs a huge AC, it might pose some issues in the long run.

One of the biggest problems is that larger units require a lot more energy to operate. Energy bills will increase because of this. Larger units operate by short cycling frequently, which causes the compressor to turn on and off most of the time and is not particularly energy efficient. Thus, knowing the right size AC unit for a specific area is one small step to compensate for its underlying drawback.

JP Reyes

JP has been in the aircon industry for almost as long as he has been alive. As a child JP would help his tatay fix aircon units at their junk shop in Cavite. After graduating UP in the early 2000's, JP then started his own Aircon servicing business and within 5 years had 10 shops in 8 different cities. Fast forward to today and JP brings all his experience and expertise online to give readers trustworthy advice and reviews about Air-conditioning buying, servicing, cleaning and repair in the Philippines.

  • 1