What SEER Rating is Best and What Does It Really Mean?

When searching for a new air conditioner, what’s your top priority? If you’re like most of us in Arizona, the answer is “Comfort!” Our summer temperatures soar past 100°; air-conditioned homes and buildings aren’t just a nice refuge from the heat, they’re life-savers! But there are other important factors to consider.  If you don’t want your electric bill to rise right along with the temperature, efficiency is critical. So what SEER rating is best for you? Let’s take a look.

What Is the SEER Rating?

First things first: SEER is the Seasonal Energy Efficiency Ratio. It is a measurement of an air conditioner’s cooling efficiency. To calculate SEER, you divide the BTU/hs (or the cooling power for normal annual usage) by the watts (or the total energy input for that period).

SEER In Your Home

Let’s look at an example that’ll help you choose the right SEER rating:

You have a 36,000 BTU/h AC system with a SEER of 15 (you can find the SEER on the unit’s box or in the included information).  You divide 36,000 by 15 to get 2400. That means that the unit consumes 2400 watts per operating hour.

For our example, you run the AC unit 2000 hours each summer. Multiply 2000 by the watts used by the unit, 2400. This is 4,800,000 watts. Don’t panic! Your electric bill is figured in kilowatt hours(kWh). Simply divide 4,800,000 by 1000. this equals 4800 kWh. That’s better.

Ok, so your 15 SEER AC unit will use 4800 kWh per year, assuming the conditions we talked about above. Now, let’s talk dollars and cents. If your electricity is 12 cents per kWh (the average in Arizona), you can easily figure out how much it’ll cost to cool your home:

Annual Operating Cost: 4800 kWh x .12 = $576

You can also plug in the numbers to figure out the operating costs for models with different SEER ratings. Let’s look quickly at a 13 and a 23, to get a sense of the entire spectrum.

36,000 BTU/h÷ 13 = 2769.23077. We’ll round up to 2800.

2800 watts x 2000 hours = 5,600,000. We’ll divide that by 1000 to get 5600 kWh.

5600 kWh x .12 cents per hour = $672

As you can see, the 13 SEER is more expensive to run. Now the 23:

36,000 BTU/h ÷ 23 = 1656.21739. We’ll round to 1700.

1700 watts x 2000 hours = 3,400,000. Divided by 1000 is 3400 kWh.

3400 kWh x .12 cents per hour = $408.

You may be tempted to get the biggest SEER, but remember, these units increase in price as their SEER rating increases. A 23 SEER can cost twice as much as a 13 or 16. You have to factor in the initial and installation costs, as well as how long you plan on owning the unit. Will you have it long enough for it to repay your investment?

Ask your heating and cooling specialists at R&R Refrigeration to recommend a unit that’ll keep you cool without burning a hole in your wallet.