So you’ve determined that you need a new air conditioner in the Greater Hamilton area. You understand that there are different SEER ratings, but you are not quite sure what that means for your pocket book. Let’s start with the basics. First of all, SEER stands for Seasonal Energy Efficiency Ratio. The higher the SEER rating, the more energy efficient a given air conditioner is. Great, but now you have to know how to determine how much a 13 SEER saves versus a 14 SEER, or a 16 SEER–and so forth. How much you’ll save depends on several factors, such as; amount of insulation in the home, quality of windows, proper sizing etc. For demonstration purposes, let’s assume that all is adequate and the unit is sized properly.

To determine how much each SEER rating will cost to run, you will need a few tools.  You will need to know how many hours you run your air conditioner annually, what the size (BTU’s) of the unit is, the SEER rating of the unit and cost of hydro per KWH.

Here’s how to determine energy consumed (watts)

Divide Btu’s produced by the stated SEER rating

Ex. 24,000 Btu (2 ton) divided by 13 SEER = 1846 (watts)

Convert this figure to Kwh (1000 watts per KW)

Ex.1846 watts divided by 1,000 = 1.9 Kwh (rounded up)

We will use 1,700 annual hours of operation as an example

Multiply the number of Kwh your air conditioner consumes (1.9) each hour times the number of hours it operates annually (1,700) to determine annual Kwh usage

1.9 Kwh X 1700 hours annually = 3,230 Kwh annual consumption

3,230 x 11 cents cost per Kwh (example) = $355.30 annual cost of operation for a 2 ton, 13 SEER air conditioner.

Now, let’s compare that to a 16 SEER, 2 ton unit under the same circumstances.

24,000 Btu’s divided by 16 Seer = 1,500(watts)

1,500 divided by 1000 = 1.5 Kwh consumed each hour

1,700(hours of operation) x 1.5 (Kwh consumed each hour) = 2,550 Kwh consumed annually

2,550 x 11 cents cost per Kwh = $280.50 annual cost of operation for a 2 ton, 16 SEER air conditioner.


Assuming an air conditioner lasts an average of 15 years, you can determine whether the annual savings is worth the investment in a higher SEER rating.

Langton Mechanical has been keeping families in the greater Hamilton area comfortable for over 20 years. We carry a variety of products and are always happy to assist those who require heating and cooling services.