Air Conditioning
STRATEGY: The best approach to take in staying cool for the summer is to keep the heat out with house tightening insulation, and window shading; refer to Tightening and Insulating. Next try to avoid heat producing tasks inside your home. If it is still too warm to tolerate, try some of the air conditioning alternatives offered below. If you must resort to the air conditioner, follow the operating tips below for most efficient operation. Finally, if you use your air conditioner extensively, it may pay to replace it with a more efficient model.
MYTHS ABOUT AIR CONDITIONING:
MYTH: It's more efficient to leave the air conditioner running than to shut it off and have to re-cool the house later.
FACT: You begin saving as soon as you shut off your air conditioner. If your house is tight and well insulated, it may stay cool all day. This will only work if you keep your house closed up all day. Opening the windows not only heats up the house, but also allows the humidity back in that your air conditioner worked so hard to remove. The exception to keeping windows closed is at night when it is cool outside.
COOLING TIPS:
• Wear lightweight, light colored clothing made of natural fibers. It will reflect heat and absorb perspiration, making you feel cooler.
• Drink plenty of liquids.
• Plan cold meals with cold cuts, salads, etc.
• If you are going to cook, use appliances that don't produce much heat such as microwaves, crock pots, frying pans, etc. Or enjoy the outdoors and barbecue.
• Schedule heat-producing tasks for the early morning or late evening instead of during the hottest part of the day.
• Turn off unnecessary lights and appliances.
• Keep both primary and storm windows shut when closing up the house for the day or when running the air conditioner.
• Close your drapes on hot sunny days, especially the east and west drapes. If there is some way to shade your windows on the outside this will keep out even more heat.
• Try to use as little hot water as possible. It adds heat and humidity.
• Use bath and kitchen vents to exhaust heat and moisture.
• Make sure your clothes dryer is vented outdoors. You don't need the heat or humidity inside the house. Or use your "solar clothes dryer," the clothesline.
• Turn off the pilot light on your furnace. This saves gas and heat. Ask a dealer how to turn off and relight pilot lights. Pilot lights on most gas appliances such as stoves and dryers also contribute to the cooling load. Shut off unnecessary pilot lights and light by hand when needed.
• Install reflective window films or solar screens on unshaded east and west windows. (Cost effective only if you run your air conditioner extensively, otherwise it's a comfort issue).
AIR CONDITIONING ALTERNATIVES:
• Open your windows in the evening to capture the cool breezes and close them early in the morning on hot days. If your home is tight and well insulated, it may stay cool all day.
• If your basement is livable temporarily move downstairs on hot summer days. It is often 10-15 degrees cooler than the upstairs.
• Use fans whenever possible.
• Install a whole house fan (only works if it is cooler outside than inside) and provide a good cover to seal it in the winter.
• Install a ceiling fan to create air movement. The air movement can keep you cool at a higher temperature, allowing you to avoid running your air conditioner or letting you set the air conditioner temperature higher.
OPERATIONAL TIPS:
• Set the thermostat at 78 degrees. Each degree higher saves approximately 6 percent on air conditioning costs.
• Don't turn the thermostat lower than the desired setting. The house will not cool off any faster and can overshoot the desired temperature, wasting energy.
• If the house is unoccupied during the day, you will save energy and money if you turn off your air conditioner and leave your house closed up. It may stay cool all day. If not, and you don't like coming home to a warm house, purchase a clock thermostat to turn on the air conditioner in time to have the home cool when you arrive.
• Don't run your air conditioner all night if it is cooler outside than inside. Open the windows and use the fan.
• Turn off the air conditioner if you're leaving the home for more than an hour.
• Keep grills and heat exchangers clean and filters frequently changed.
• Clean the unit before each cooling season (See manufacturer's instructions).
• Shade the outside compressor unit but don't block the air circulation.
INSTALLING A NEW AIR CONDITIONER:
• Install a new medium to high efficiency air conditioner. Efficiency is measured in SEER (Seasonal Energy Efficiency Ratio or Btu/watt). The higher the SEER the more efficient the air conditioner.
*The items marked with an asterisk (*) are, for the most part, only marginally cost effective and may be done for reasons other than energy savings.
