EER vs. SEER: A Short Guide

You will likely come across Energy Efficiency Ratio (EER) and Seasonal Energy Efficiency Ratio (SEER) when searching for the right air conditioner for your Bay Area home. It can be confusing to understand these ratings if you don’t know what they mean or measure. This guide will help you understand what EER and SEER are, importance of these ratios, and the best way to use them for selecting an appropriate air conditioner.

Overview of SEER

Seasonal Energy Efficiency Ratio (SEER) is the most common way of measuring the efficiency of an air conditioning unit. It measures the efficiency of an air conditioner and how it operates over the season. The primary difference between EER and SEER is that SEER measures the operational efficiency of the air conditioner over an entire season.

SEER rating is calculated and tested based on a variety of outside temperatures. This can range from 65 to 104 degrees Fahrenheit. This calculation is designed for providing a climate specific measure of efficiency. It is mainly useful in the middle of the US, but holds an importance to Californian homeowners as well. Further, SEER is associated more commonly with central air conditioning units.

What Does EER Mean?

EER or the Energy Efficiency Ratio is a standardized measurement of an air conditioner’s energy efficiency. While comparing air conditioners, you should always opt for a unit that has a higher EER. Higher EER means that the unit is more efficient in terms of energy consumption.

It is also important to remember that EER basically measures the efficiency of the air conditioner at a single operating temperature. Specifically, EER measures an HVAC unit’s efficiency when the outside temperature is 95 degrees F. This is different from SEER that takes into account a broad range of outside temperature.

Ratings Really Matter

SEER and EER provide essential and useful information to homeowners deciding on a new air conditioning unit. All new air conditioners come with Energy Guide labels attached in a visible place. You should take note of the following pieces of information when looking at the label:

• Estimated annual energy cost: This rating will tell you the cost of operating the air conditioner every year. This particular cost is based on the national average electricity cost and is calculated by comparing with similar capacity models.
• Appropriate ratio: You should see the EER listed on the label if purchasing a room air conditioner. SEER will be displayed on the label for central air conditioner systems.
• Energy Star: Energy Star seal will be available on the unit if it has undergone independent verification and meets rigorous efficiency standards. Products with the Energy Star seal are some of the most cost-efficient HVAC units on the market.

Comparing with Similar Models

You should know that the EER and SEER ratings of air conditioners doesn’t allow for useful comparison. You will not find any relevant information in comparing EER with SEER ratings. You should compare the EER of an air conditioner against the EER of another. The same holds true for SEER ratings if you are planning on purchasing a central air conditioner. Air conditioning units with higher EER and SEER ratio are more efficient as compared to other units.