Sizing A Central AC System

Denver Air Conditioner

When shopping for a central AC unit for your home, one important factor that you might not have considered is unit size. The fact of the matter is that the size of your AC unit is of vital importance when it comes to ensuring that your home is properly cooled and your family is comfortable. Running an AC unit is expensive thanks to the cost of electricity today, so you don’t want to waste money running a unit that is bigger than it needs to be. On the other hand, if your unit is too small, it won’t have the power to cool your house adequately no matter how much you run it.

Here are some factors to keep in mind that will help you make a decision when purchasing an AC unit.

What Does “Size” Mean?

You might think you already know what the term “size” refers to in the HVAC world—and perhaps you do! But it’s an important detail to get right. When we talk about the size of an AC unit, we are not talking about its physical dimensions. You can’t tell by looking which AC unit is the biggest and which is the smallest. Rather, AC units are measured by their ability to produce cold air, marked in BTU (British Thermal Units) per hour. The higher the BTU, the bigger in size we say the unit is. And a unit with a high BTU will be capable of providing more cooling energy.

Factors that Affect Your AC Unit Size

Before selecting an AC unit, it’s a good idea to consult with an expert and make sure you’re choosing the right size. Your expert will analyze your home and consider the following factors before making a recommendation:

  • The volume of your home—all the living space that must be cooled. This is more than just square footage. The height of your ceilings matters too. A small room takes less energy to cool than a spacious one.
  • How many exterior walls are exposed to sunlight—and how big those walls are. Exposure to sunlight increases the ambient heat in your home.
  • Your window quality. Do your windows leak? Do they face the sun?
  • The age of your home. Older homes have more trouble retaining cold air.
  • The ventilation and ductwork, and whether these factors are set up in your favor already.
  • Whether your home is receiving shade from nearby trees and bushes.

If you need help deciding what AC unit to buy, contact us today!  

What Is A Load Calculation?

At some point in your life, you’ve visited someone’s home and thought to yourself…

“Why in the world is it so hot/freezing cold in here?!”

Perhaps the homeowners simply have no sense of comfortable temperature. But don’t place the blame just yet. The truth is that the majority of heating and cooling systems installed in homes today are oversized and inefficient simply because the contractor who installed it did not perform a proper Manual J Heat loss/Heat gain calculation. Load Calculations are THE ONLY acceptable way to size a furnace, boiler, or air conditioner. Oversizing causes poor efficiency, subpar comfort, and premature equipment failure. Make sure your contractor takes the time to do one! A few minutes now will prevent years of headache, frustration, and added costs!

How to Formulate Load Calculation

You should always enlist the help of a professional when measuring load calculation. Chances are, you can’t walk into your home, evaluate its needs and determine it needs a new four-ton system.

When you hire a professional, he formulates your load calculation by evaluating a number of different things:

  • How many people live in the home.
  • The size of the home.
  • The insulation values of walls, attics, windows, and skylights
  • Orientation of the home
  • Appliances in the home

It’s no surprise that larger homes need larger, stronger systems. Whereas, smaller homes require smaller systems. Every home is unique in these factors listed above and should not be generalized simply by square footage.

Other Factors to Consider

In addition to occupancy and home size, you’ll need to consider a few other factors. Each of these things play an important role in formulating the load calculation of your home.

Outside Temperatures

The temperature outside will play a huge role in how hot or cold you want your home. This becomes even more important when you live in areas with extreme temperatures. A poor load calculation could leave your home smoldering in hot areas or freezing in cold areas.

The Importance of Air Control

Many don’t consider what happens as a result of too much air control. With too little, you don’t have enough heat. But with too much, you’ll experience problems as well.

Because the system overworks itself, the house will get way too hot or cold. It can also wear out faster due to overuse.

Both of these issues result in unnecessary financial burdens. No one wants to replace their system or suffer with inordinately high energy bills every month.

Does Your Home Have Proper Load Calculation?

Take the time to get a professional estimate. They will evaluate the factors to determine the efficiency of your system. A system designed by a load calculation will keep your home comfortable and energy efficient.

Invest in an estimate today.