Even though our air conditioning season is relatively short, we all can attest to how important a properly operating air conditioner is. When selecting an air conditioning system, just like a gas furnace, you want it to both save you money and be comfortable.
Like your gas furnace, more than likely your air conditioner is single stage. When your thermostat calls for cooling, you air conditioner comes on at 100% output. Air conditioners are sized to keep your home at 75F inside when it is 90F outside. Historically, it is only over 90 degrees outside just 1% of the time. (Although this summer it seems like all the time!). So, anytime it is running when it is less than 90F it is essentially oversized. Just like the multi-stage furnace, the multi-stage air conditioner solves this problem. The air conditioner reduces its output to match the need. The air conditioner runs longer with less energy usage and increased comfort.
Due to a recent government mandate, all air conditioners manufactured must now be 13 SEER efficiency. SEER stands for season energy efficiency ratio, similar to AFUE for a furnace. This is almost like a miles per gallon rating for your car. The higher the SEER, the less energy the system uses in order to cool your home. More than likely your air conditioner is rated at 10 SEER or less. So, if you purchase the minimum efficiency air conditioner today, it will use 30% less energy! For this reason, we typically recommend purchasing a 13 SEER air conditioner or the minimum you can buy, and investing the savings into a humidification system, high efficiency filtration, or a full feature thermostat.
You already know how your heating and air conditioning system works in your car. Watch the video to see how your home system compares:
If an air conditioner is oversized, you will not be comfortable. This can actually make you less comfortable than when it is undersized. The longer the air conditioner operates the more humidity it is able to remove. If the air conditioner is oversized, it will satisfy the thermostat temperature quickly, leaving the air at the right temperature, but not the right humidity. Humidity is one of the four elements of comfort. Learn about the four elements of comfort here.
Residential air conditioners are called "split-systems" because they have two major components, the outdoor condenser and the indoor evaporator. When we think of the air conditioner, we usually are referring to the outdoor component, the condenser. Although this coil is encased in sheet metal and hides behind the scenes, matching this to your outdoor condenser is vitally important. You cannot replace the outdoor condenser without changing the indoor evaporator coil unless they were designed by the manufacturer to work together.