The Stiles Blog

Does size really matter? When it comes to your air conditioning unit, the answer is YES! Don’t fall for the myth that bigger air conditioning units are better. In fact, they do not give you better results.

So why is it important to get the right size? Here are four reasons:

1. Comfort
   Air conditioners cool your home and dehumidify it, the latter of which takes longer to accomplish. However, when you have an oversized air conditioning unit, it won’t run for very long because it will cool off the house quickly and then turn off, not having a chance to fully dehumidify the house.
2. Extra wear and tear
   Your HVAC equipment gets worn out faster by constantly starting up and shutting down. This means the lifetime of your equipment will be shorter as well. As we discussed in reason one, an oversized air conditioning unit only runs for a short time because it cools off the house quickly and then shuts off. This cycle is repeated over and over throughout the day, starting up and shutting down much more often than a properly-sized air conditioning unit. This extra wear and tear means you’ll likely have more repairs, and you’ll be replacing the unit altogether sooner rather than later.
3. Cost
   Not only does an oversized air conditioner cost more to purchase, but it costs more to run, will likely need more repairs and will have a shorter life because of the way it runs.
4. Indoor air quality
   When you have an oversized air conditioning unit, your indoor air quality is not optimal because the unit runs for shorter periods of time. Why does that matter? When your unit runs for shorter periods of time, it doesn’t filter the air as well as a properly-sized air conditioning unit would. This means it doesn’t remove pollutants from your home’s indoor air as well (think contaminants like dust mites, mold, pet dander, dead skin, allergens, viruses and more). For more information on indoor air quality, see this “Care for Your Air” guide from the United States Environmental Protection Agency (EPA).

Just as you don’t want an oversized air conditioning unit for your home, you also don’t want a unit that is undersized to cool your home because it will run constantly, trying to cool the entire house, and will run up your energy bill. A properly-sized system will work much more efficiently to cool your home, not running too little or too much. It will help your energy bill and make your home less susceptible to moisture issues.

So how do you decide what the best size air conditioning unit is for your home? There are many factors that go into making this decision, such as your home’s square footage, ceiling height, the type of insulation you have, the type of windows you have, the climate in which you live, if you have a basement or slab, what color your roof is, etc.

It is best to have an HVAC professional identify the best size system for your home. They will calculate the required size for your air conditioner by doing a Manual J load calculation, which is a detailed analysis of your home’s central air conditioning and heating needs based on factors like the ones mentioned above.

Call Stiles Heating, Cooling, & Plumbing today to help you select and install the best size air conditioning unit for your home and your family’s health, comfort and wallet.