Terms To Know When Shopping For A New Air Conditioner

Posted on: 10 June 2020

When you start shopping for a new air conditioner, you might notice a host of new lingo associated with different systems. The first step in finding a good unit for your home is to understand these terms. With that knowledge, you can choose a system that fits your home's needs and your energy efficiency preferences. Below are some of the most important terms related to AC systems.


BTU is the acronym for British Thermal Units. It's the measurement used for the amount of heat needed to raise one pound of water's temperature by one degree Fahrenheit. Your home's size dictates the number of BTUs needed to cool your rooms.

You want to hire HVAC experts to do an analysis of your home to determine the exact size of the unit you need, as measured in BTUs. However, Consumer Reports recommends a general 20 BTUs per square foot.


As related to air conditioners, the term ton relates to its size and cooling capacity. In fact, it goes hand-in-hand with BTUs because each ton is equivalent to 12,000 BTUs. The term comes from the amount of heat required to melt one ton of ice in a 24-hour period.

Though the two terms measure the amount of energy needed to heat something, they do relate to cooling. So, each ton in an AC unit represents the ability to remove 12,000 BTUs of heat per hour from the house. Residential air conditioners range between three and five tons.

SEER Rating

SEER is the acronym for Seasonal Energy Efficiency Ratio. It's a measurement of the unit's energy efficiency. Manufacturers use a formula to rate the unit. They consider the cooling output divided by the unit's electric input.

You typically find the SEER rating in a red box near the rest of the unit's specifications. The ratings range from 13 to 25 with higher numbers representing more energy efficiency. A 13 rating is the minimum for most states, though hotter states may require a 14 rating.

AHRI Certification

AHRI is the acronym for Air Conditioning, Heating, and Refrigeration Institute. It's a trade association that sets the terms for SEER ratings. It also puts out its own certification on HVAC units related to performance.

The institute has developed standards for measuring and certifying product performance. Manufacturers can test their HVAC units according to these standards. If they pass the appropriate measures, they can carry an AHRI certification, which tells you that the unit will perform consistently.

Shop for your new AC unit armed with the above terms related to performance and efficiency. If you have any questions while shopping, consider reaching out to an HVAC Company.