What Size Air Conditioner Do I Need?
A lot of people don’t have any idea of what size of air conditioning unit to purchase for their homes whenever they need to provide a cool temperature inside their house. According to an article by Energy Star, most of us will just grab the biggest unit that we can find, thinking that a large air conditioning unit can provide better cooling for our family.
However, the reality is that purchasing an oversized air conditioning unit is less effective in providing efficient cooling for our homes, explains Superior HVAC Austin, an excellent choice for AC repairing in Austin. At the same time it can also waste us a lot of money on electricity bills.
Why it is Not Advisable to Purchase an Air Conditioner that is too Large For the Room?
An air conditioner functions by removing humidity and heat from the air. Because of this, using an air conditioner that is too large for the room that it is intended for will make the air in the room feel damp and clammy because it will cool the room to0 quickly which will inadvertently leave some humidity behind.
In addition to that, a larger air conditioner needs more power to operate and thus will consume more energy than what is needed to efficiently cool the air inside your house.
The most effective thing to do is to acquire a properly sized air conditioning unit that can remove heat and humidity properly and at the same time use the right amount of energy that is needed in order to cool the room.
The truth is that the physical size of an air conditioner doesn’t really determine its effectiveness. What matters is its cooling capacity which is measured in BTUs per hour.
Before we go further, let us get a better understanding of what a BTU means.
What Are BTUs?
According to Wikipedia, BTU or British Thermal Unit is a unit of measurement that is equivalent to the amount of heat that is needed for the temperature of a pound of water to increase by one Fahrenheit. This unit of measurement is the standard cooling capacity used to determine the power of a particular air conditioning unit.
Now that we know what BTUs are, let us now calculate the power of the air conditioning unit that we need that is appropriate for the room that it is intended for.
How to Determine the Right Size of Air Conditioner to Purchase?
To begin with the calculation, we need to compute for the square footage of the area of the room where the air conditioner is going to be placed.
To do that, you need to use the following formula:
Square and Rectangular Rooms
Multiply the measurement of its length with the measurement of its width.
Multiply the measurement of its length with the measurement of its width then divide it by two.
For Other Room Shapes
Consult a sales associate of the store that you are planning the purchase to help you compute the square footage area of your room.
Now, after you have determined the size of the room, select the appropriate BTUs per hour needed based on the data given below:
Area Size (Square feet) BTU per hour
100 to 150 5000 Btu/h
150 to 250 6000 Btu/h
250 to 300 7000 Btu/h
300 to 350 8000 Btu/h
350 to 400 9000 Btu/h
400 to 450 10,000 Btu/h
450 to 550 12,000 Btu/h
550 to 700 14,000 Btu/h
700 to 1000 18,000 Btu/h
1000 to 1200 21,000 Btu/h
1200 to 1400 23,000 Btu/h
1400 to 1500 24,000 Btu/h
1500 to 2000 30,000 Btu/h
2000 to 2500 34,000 Btu/h
After selecting the Btu/h required to efficiently cool the room in normal circumstances, you will now have to add or subtract BTUs from it based on the following scenarios:
Heavily shaded room Reduce Btu/h by 10%
Very sunny room Increase Btu/h by 10%
More than 2 people occupying the room Add 600 BTUs per additional person
Kitchen Area Add 4000 BTUs
After that, the resulting Btu/h is the recommended air conditioning unit capacity that you should buy to efficiently cool the room that you computed for.
Other Features to Consider When Buying an Air Conditioner for Your Home
Besides the cooling capacity of an air conditioning unit, it is advisable to choose one that has two or more of the following features:
- Programmable timer
- Sleep settings
- Electronic ionizer
- Venting option
- Remote control
- Extra-long cord
- Filter alert
The ability to compute and determine the cooling capacity of an air conditioning unit that is appropriate for a particular room will not only make your room cooler and the air fresher but it can also save you a lot of money in terms of electricity bills that are saved in the long run.