Experienced HVAC contractors at Cuesta’s Air Conditioning & Heating can help choose the correct size AC unit for any home or business. One of the most common questions we are asked by our customers is “What Size AC Unit Do I Need?” First of all, we need to visit the location in order to assess the situation. In addition to our own observations, we ask a series of questions that can help determine the correct AC unit size for the specific situation.

AC Unit Size Factors

Many of the factors are taken into consideration before recommending a specific AC unit size. In order to properly choose the right size air conditioner, a professional HVAC technician will need to come to your location and provide a total assessment. Here are common factors that will affect your home’s cooling when it comes to choosing an AC unit size:

1. Total volume of the home or business living space (not just square footage)
2. The age of a home or building construction
3. Amounts of air-sealing insulation
4. Existing ventilation system and ductwork
5. The amount of sunshine on your home, including areas sun-exposed exterior walls
6. The number, age, condition, orientation of windows and the direction they face

Air Conditioning BTUs Needed Per Climate Zone

We’ve provided climate zone map of the U.S. below in addition to the BTUs needed per square foot. BTU (British thermal unit) is a traditional unit of heat. Because Florida is in the hottest zone, homes and businesses need adequate central air conditioning systems. For example, if you live in a 3,500 square foot home in Florida, which requires at least 50 BTUs per square foot, then you need an AC unit with an output of 175,000 BTUs per hour. The efficiency of the HVAC system is also a factor to take into consideration. Our highly-trained HVAC contractors are here to provide the knowledgeable guidance to help you choose the right AC unit size.