The bigger the air conditioner, the better it will work to cool your home, right? This common misconception has gotten many homeowners into trouble when trying to figure out what size air conditioner is best for their home. Air conditioners that are too large for your home will not run long enough to remove moisture from the air, and units that are too small will work overtime to try to maintain the cool temps in your house. Luckily, there’s a formula to help you determine which size is best for your home.
The formula for AC Size
Air conditioners are sized based on BTU, British Thermal Units, not the size of the physical unit. To determine the right BTUs for the central air conditioning system in your home, take the area of the home multiplied by 25 BTUs. If your home is 2,000 square feet, you’ll need to multiply 2,000 by 25 to get 50,000 BTUs needed. If you are using a window air conditioning unit, you will determine the size you need based on which room you are trying to cool. Just like with the central air conditioning system, you’ll take the area of the room multiplied by 25 BTUs to determine the correct size for your needs.
What You Need to Know About Too Small vs. Too Large AC Units
A smaller BTU size ac unit will be cheaper and might work well for cooling small rooms, but if the unit has to run continuously to keep temperatures down, you’ll see your electric bill skyrocket. You also might not be able to cool the room efficiently, especially if doors are left open, or the room is open to other areas of the house.
When you choose an air conditioning unit that is too large for your home, you’ll see the humidity in your home rising, which can cause condensation in your home, mold, and mildew growth. Air conditioners do more than cool; they remove moisture from the air to keep the indoor climate-controlled and comfortable. Too large AC units will also turn on and off frequently, causing more wear and tear on the machine and thus shortening its lifespan.
If you are still struggling to decide which size air conditioner is best for your home, consider contacting a professional HVAC company that can send out someone for an estimate. A professional can also help you determine whether central air is a possibility for your home, or if you should stick with window or wall-mounted units.