Whenever you are considering replacing your HVAC system, it would be safe to assume that you can just replace it with one of the same size, right?

“I have a 4.0 ton HVAC unit, so I need to replace it with another 4.0 ton.”

If you go with the same size as the previous system, then you have to be willing to trust that the previous system’s installer sized it properly for your home; and it’s not as simple as just getting the square footage. In order to make sure that you get the most bang for your buck with your new HVAC system it must be sized properly for your home’s specific needs.

 

HVAC Unit Sizes

Heating, Ventilation and Air Conditioning units are sized based upon their BTU rating. The smaller the BTU rating, the smaller the space it will efficiently heat and cool; and vice versa. While this is important information to help determine the correct system for your home; it isn’t the only factor to consider when deciding what size unit to go with. For example, the age of your home and how well it is insulated plays a part in how well a system can condition the air within.  Your main floor’s calculations are performed differently if you have a two-story house. And the energy efficiency and size of your windows can also change the heating and cooling load of your home.

 

Why the Size of the Unit Matters

Choosing a custom system sized specifically for your home is important for many reasons. If a system is sized too small, it may not be able to keep your home warm enough in the winter or cool enough in the summer. And even if it does manage to maintain a comfortable temperature, an under-sized system will have to work harder to keep you comfortable, consuming more electricity. The same principle applies to an over-sized system. It will consume more energy than necessary to condition the air within your home, and will actually condition your air too quickly to do it correctly. An HVAC system needs to run long enough to lower or raise the temperature of the air and adjust the humidity of the air properly; without running longer than needed. An overworked system consumes more power, has a greater chance of requiring repairs and a decreased lifespan.

 

Knowledge is Power

While BTU charts are available online to estimate the correct size for the system you need for your home, most of these will only determine this based upon your home’s square footage. When you are getting quotes for your new HVAC system, make sure your potential installer isn’t basing your investment on the professionalism and expertise of whoever installed the last one; or that their only tool for determining your needs is a measuring tape.

If you would like a free professional assessment and recommendation for your home’s HVAC system, please feel free to give us a call at 256-858-HVAC (4822).