Sizing Air Conditioners
When the summer heat sets in, you will be relying on your air conditioner to keep you cool and comfortable. Just remember, don't overdo a good thing!
Studies have shown that one-third of home air conditioners do not work the way they should because they are oversized. And an oversized air conditioner does not mean more cool comfort for you; it means higher purchase costs, higher operating costs and a home that is too cool to be comfortable.
An oversized air conditioning unit short-cycles (runs for shorter periods of time than it should) and uses more electricity than a properly sized unit. Air conditioners operate more efficiently the longer they run continuously. They should be sized so they do not turn on and off frequently on hot days. An oversized air conditioner that runs for only short periods of time makes your house uncomfortable because it cannot dehumidify the air effectively. The indoor coil never gets cold enough to do its job of removing moisture from the air. That means an oversized unit will leave your home cold and clammy, especially when the outdoor air is humid.
Oversized air conditioners cost more to buy and do not last as long. Do not pay extra for an air conditioner that is too big for your house; the larger system will cost you hundreds of dollars more and give you fewer years of service.
Contractors should calculate how much cooling a home needs according to guidelines such as the Air Conditioning Contractors of America's Manual J. A contractor should not size your unit solely on the square footage of your home. To gather the information necessary, a contractor should spend some time poking around your home, taking measurements and asking questions.
Do not be tempted by the lowest bid. Be willing to pay for the time the contractor must spend to do the job right.
If you are considering replacing your air conditioner, buy a high efficiency unit. Central air conditioners are rated by SEER, or Seasonal Energy Efficiency Ratio. Klickitat PUD recommends air conditioners with a SEER of 11 or higher to get the best energy efficiency.
Heat pump for summer comfort
Does your furnace need replacing? Consider installing an energy efficient heat pump system. They provide year round comfort -- even, comfortable heat in winter, and central air conditioning in summer.
A heat pump is the most efficient form of electric heat because it provides three times more heat than the equivalent amount of energy it consumes. That is because a heat pump takes heat from outside and moves it inside to heat your home.
There are three types of heat pumps: air-to-air, water source, and ground source. They collect heat from the air, water, or ground outside, concentrate it and pump it inside. Because it works by collecting heat rather than creating it, a heat pump can cut the amount of electricity you use for heating as much as 40 percent.
As a bonus, in summer the heat pump does double duty as an air conditioner. It actually reverses itself and cools your home by collecting the heat from inside and pumping it outside.
To learn more about home cooling, contact Anita, Klickitat PUD's Energy Services Specialist. You can call her at 509-773-7622 or toll-free at 800-548-8357.