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When it’s time to install a new air conditioning system for your home—whether it’s the first system or a replacement for an older one—you’ll face a number of decisions. There are different factors to consider when selecting a new AC, and one of them is energy efficiency, i.e. how much energy the air conditioner uses compared to how much cooling power it outputs. There are two measurements of air conditioning efficiency listed on a system: EER rating and SEER rating. We’ve put together a short guide to understanding the meaning of these ratings—and what they mean for your air conditioning installation.

At Freedom Heating & Air Conditioning, Inc., it’s our goal to make long-lasting relationships with our clients by exceeding expectations and earning their trust. When you’re planning for an air conditioning installation in Minneapolis, MN or elsewhere in the Minneapolis-St. Paul area, make us your first choice.

What Does an AC EER Rating Mean?

EER stands for energy efficiency ratio. EER is a ratio of the amount of cooling an air conditioner creates (measured in BTUs) to the amount of electrical power the unit consumes (measured in watt-hours). In other words, divide the cooling output by the electrical consumption, and you have a number you can use to compare a system’s efficiency to that of systems. A high EER rating means a more efficient system. The typical conditions for calculating EER are an outside temperature of 95°F and an indoor temperature of 80°F with 50% relative humidity.

How Is an AC SEER Rating Different from an EER Rating?

The difference between the two is the important first letter: S for seasonal. The SEER rating is the same ratio of “output to electrical consumption” as the EER rating, with a high SEER rating indicating higher efficiency. But where EER is measured during one test under specific temperature conditions, SEER is calculated for the entire cooling season with its swings in temperature and humidity, with outdoor temperatures from 64°F to 104°F. You could say that SEER is a reflection of how EER changes under different conditions.

Which of the Two Is More Important for AC Installation?

When it comes down to EER vs SEER, what’s the answer? Is a high SEER rating more important, or is a high EER the number to pay attention to?

The answer is that SEER should be weighed heavier, but EER shouldn’t necessarily be ignored. You can get a sense of the general efficiency of an air conditioning system based on SEER, since you’ll use your AC during the entire season. But EER is helpful since it provides a snapshot of performance during peak summer condition. (Never compare the SEER of a unit to the EER of another, however. Compare SEER to SEER, and EER to EER.)

SEER Air Conditioner and EER Air Conditioning Selection

High efficiency is only part of choosing a new AC. Making an air conditioner unit choice based only on a high SEER or EER rating can lead to picking the wrong type or size of unit. Working with a professional technician is necessary to see that all the important factors are weighed and that you end up with an ideal new home air conditioning system.

We must emphasize this: don’t make a choice for a new air conditioner without the assistance of skilled HVAC professionals. Contact Freedom Heating & Air Conditioning, Inc. and let our technicians handle the work of matching your house in Minneapolis, MN to the perfect new air conditioning system. Give us a call to schedule air conditioning services in Minneapolis, MN and the surrounding area.

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