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What Size AC Unit Do I Need? 10 Factors That Affect Sizing

Serving Families Throughout Dallas
variable speed air conditioning units

As HVAC experts, we get a lot of customers asking us about air conditioning unit size and what size unit they should have for their home. The honest answer is that the right size can vary according to each home’s unique cooling challenges. Below, we’ll explain how air conditioner “sizing” works and what factors should be considered when determining the air conditioner size your home needs.

First, It’s Not Really “Size” – It’s Cooling Capacity

When most people ask “What size air conditioner do I need?” they’re usually not referring to the actual feet and inches of the unit. They’re talking about the cooling capacity: the AC unit’s ability to cool a space.

Air conditioner cooling capacity is expressed in tonnage (ex. 2.5 ton, 3 ton, etc.). Tonnage ranges from 1.5 to 5 tons, and those ratings matter a lot in terms of how well an air conditioner can perform in your home.

So you’re probably wondering, what tonnage should my AC have for my home? While your home’s square footage impacts the size your AC should be (or rather, the tonnage it should have), there are other factors involved, which we’ll explain below.

10 Factors That Affect How Much Tonnage Your AC Should Have

When determining what size (or cooling capacity) your air conditioner needs, there are potentially several factors to take into consideration. For this reason, we highly recommend that you always get an in-person estimate on an AC system before agreeing to any installation.

Here are some factors that can affect what tonnage your air conditioner will need to perform efficiently and effectively:

  1. Square footage of your home’s interior
  2. How many stories your home has
  3. How many windows and doors your home has
  4. How well your home is air-sealed and insulated
  5. Number of heat-generating appliances
  6. Size of your current household
  7. How much direct sunlight your home gets – and at what time of day
  8. The region in which your home is located
  9. Additional features that can add to heat loss and gain (ex. skylights, fireplaces, etc.)
  10. What material your home’s exterior is constructed from

Thorough Estimates on AC Installations

At Rescue Air and Plumbing, we pride ourselves on providing our customers with comprehensive in-home estimates on new HVAC systems. We want your new air conditioning system to be your match made in heaven. Schedule your estimate today online or by calling us at (972) 201-3253.