Understanding Air Conditioner Ratings: EER, SEER & BTUs

This blog explains these key terms and helps you select the right system for your home.

What is an EER Rating?

The Energy Efficiency Ratio (EER) measures how efficiently an air conditioning unit operates when the outdoor temperature is at a specific level (usually 95 °F). It calculates the ratio of output cooling energy (in BTUs) to the input electrical energy (in watts). This rating is determined under specific conditions: an outside temperature of 95 °F, and an inside temperature of 80 °F with 50% relative humidity.

How Does SEER Rating Differ?

The Seasonal Energy Efficiency Ratio (SEER), on the other hand, measures the efficiency of an air conditioner over an entire cooling season. It is calculated by dividing the cooling capacity during a typical cooling season by the total electric energy input during the same period. Unlike EER, SEER gives a more comprehensive view of an AC system’s efficiency over time. As of January 1st, 2023, Florida residents must have a minimum SEER rating of 15 or above, which will mean slightly higher upfront costs, but lower energy bills in the long run.

EER vs. SEER: Which One Should You Consider?

While both ratings are important, HVAC technicians often recommend considering the EER rating over SEER. The reason is simple: EER is a standardized measurement and is specific to each machine, making it easier to compare different A/C systems. However, SEER ratings can help in determining which products are best suited for your geographical location. Once you've shortlisted units based on SEER, you can then compare their EER ratings to make a more informed decision.

The Role of BTUs in Air Conditioning

BTU, or British Thermal Unit, is another critical term in the world of air conditioning. It measures how much heat an air conditioner can remove from indoor air, usually within one hour. This measurement helps in understanding the power needed for an A/C unit to cool a specific area. Matching the BTU rating with your home’s square footage is essential for energy efficiency and effective cooling.

Let Crowther Roofing and Cooling Help You

Choosing the right air conditioner can be daunting with all these ratings and measurements. We understand this complexity at Crowther Roofing & Cooling and are here to help. We can take the worry out of understanding these ratings and will find the best AC system that suits your needs. Call 239-539-5850 to learn more.