How to Calculate the Required Air Conditioner Size

Before you start looking for an air conditioner, you must follow a few steps to ensure you buy the correct size. If you buy an air conditioner that is too small for a room, it will not cool as well and may never shut off. If you buy one that is too large, you will waste money and energy. Learn how to calculate the required air conditioner size and buy the right unit for the area you want to cool.

Instructions

1. Measure the room you will place the air conditioner in. Do not forget the closet space if you leave that door open often. Measure the length and width of the room.

2. Multiply the width by the length of the room to find the square footage of the room. This measurement will be what you use to find the correct size air conditioner.

3. Select the air conditioner that will cool your room. If you have a 350 square foot room, you would need an 8,000 BTU air conditioner. Use a BTU chart to determine the size of the air conditioner unit you need (see link in References).

4. Add 1,000 BTUs to the unit size if more than two or three people will be in the room at a time. If you have more than two windows, add another 1,000 BTUs unless you plan to keep the blinds or drapes closed to keep the sun out.

5. Measure the window that the air conditioner will fit into. If the window is too small for the size unit you need for the room, you may need to look at central air or a portable vented air conditioner.

Tips & Warnings

• Bigger is not better when sizing the air conditioner. It will just waste energy and cost more to run.

References

• Lowe's Air Conditioner Size Chart

Resources

• Read this Article in Spanish
• Read this Article in Spanish