Understanding BTUs And AC Cooling Power

If your air conditioner has recently died, then you may be looking for a replacement. When looking at your options, you may have noticed that many of the devices list the cooling capacity in BTUs. This unit of measurement is quite foreign to a lot of people. Keep reading to learn about BTUs, what they are, and how you can figure out how many you need when shopping for an air conditioner replacement.

What Is A BTU?

The acronym BTU stands for British thermal units. You may know that thermal means heat. This indeed is true, and one BTU refers to the amount of heat it takes to increase the temperature of one pound of water one degree. BTUs are traditional measurement units that are used to describe energy, and while it does refer to heat, the term BTU is often used as a measurement of energy.

When it comes to air conditioners, it is best to think of BTUs as a unit of heat removal. So, energy is consumed to remove heat from the air, and the amount of heat removed, and the corresponding BTUs tells us how much cooling power the unit has.

If you are confused about this measurement, then you can think of BTUs in terms of tons. A ton refers to heat transfer. Specifically, the amount of heat it takes to melt a ton of ice within one day. One ton is equal to about 12,000 BTUs. Also, one ton of heat transfer is equal to 3.5 kilowatts of energy.

How Many BTUs Do You Need?

Now that you understand BTUs, you may still wonder how many BTUs you need to cool your home. As previously mentioned, 12,000 BTUs is equal to one ton, so it may not be surprising to learn that you need quite a few BTUs to cool your home. Oftentimes, units will come in one-half, one, and two ton units. This works out to be 6,000, 12,000, or 24,000 BTUs of power. Generally, you want 6,000 - 8,000 for a smaller home and 12,000 BTUs for an average size one. A two ton unit or a 24,000 BTU device is good for a larger home.

You not only have to think about the square footage of your home, but the average temperature of your house in the summer and how much you want to cool it. Basically, if you have a smaller home, but experience temperatures over 100 degrees during the hottest months, then it may be wise to purchase a 12,000 BTU unit. In some cases, 8,000 BTU units are available, and this may work for you as well.