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The fan consumes only one-tenth the energy of the compressor, but when it runs continuously, the fan can cost up to $30 a month.
"This amount can be reduced by cycling the fan only when it's needed," Meyer said.
Additionally, the air conditioner will dehumidify the air when the compressor is running.
"If the fan remains on after the compressor cycles off, however, some moisture will evaporate," Meyer said. "This moisture must be removed during the next compressor cycle, which increases the energy consumption."
If air distribution is poor within the home or business and hot spots or very cold areas result, the fan can be run to even out the temperatures.
"The fan should be set to the auto position, however, when the building is unoccupied," Meyer said. "Even better, shut the air conditioner off or raise the thermostat setting when you leave the building."
"All air conditioners should be checked before each season's operation," said Gene Meyer, extension specialist in small business energy at Kansas State University. The check should include the following items.
1. Check to see that all filters on the air-handling systems are clean.
"They should be washed if they are a washable type or replaced if they are disposable," Meyer said.
2. The condenser unit, the unit setting outside the house, also should be checked for obstructions of the coil.
"If the coil is dirty, it should be cleaned thoroughly. Have a refrigeration technician clean the coils if heavily soiled. If there is only light dirt or dust, you can flush the coil with a garden hose. Be sure to shut power off prior to cleaning.
3. In most cases, the refrigerant level will not need to be checked unless the unit does not provide adequate cooling or if you notice frost on and of the lines going to and from the unit. "If either of these cases exist, I would recommend having a service technician check the refrigerant levels in the system," said Meyer.
Individuals can obtain the list of individuals in Kansas who participate in this program by contacting the Radon Program at KDHE. The phone number is 800-693-5343.
"The report gives each contractor's name, company name, address, phone number and other information," Snead said. The list is also accessible on the World Wide Web at http://www.epa.gov/radonpro.
The listing service is one part of the Radon Proficiency Program (RPP). EPA established the program in October 1989 to evaluate radon mitigators and provide public information on proficient mitigators.
"By choosing a contractor from the list, you at least know that he or she has passed the National Radon Proficiency Exam, taken training and is meeting current requirements," Snead said.
Qualifying contractors are issued a photo identification card.
"This helps you, the consumer, identify competent mitigators," Snead said.
As an RPP participant, contractors must follow EPA radon mitigation guidelines. These guidelines give consumers a basis for comparing bids for service.
"Also, contractors must maintain records for the mitigation systems they install," Snead said. "The records must include date, type and results of measurements; ZIP code of measurement site; mitigation system type and plan of installation; and date of installation."
EPA does not certify, endorse or recommend any contractor, nor is it liable for any contractor's work.
"Any type of fan can be effective in reducing air conditioning costs if the air movement helps occupants feel comfortable and results in increasing the thermostat temperature setting," said Bruce Snead, extension specialist in small business energy at Kansas State University.
If the air conditioning thermostat setting is not increased, there is no savings.
The cooling effect of moving air can compensate for as much as a four-degree rise in temperature.
Before operating a ceiling fan, it is important to determine the temperature of the air at the fan height when the space is air conditioned.
"If the temperature at fan level is more than eight degrees warmer than the temperature at floor level, the added load on the air conditioner created by circulating the warmer air from the ceiling can offset the savings of increasing the thermostat setting," Snead said.
At most ceiling heights below 12 feet, the temperature difference will not be a problem. At ceiling heights above 12 feet, a thermostat should be installed at the fan height to prevent the operation of the ceiling fan when the temperature difference is more than eight degrees.
"Keep in mind that during the heating season the air movement caused by the fan will still have the same cooling effect," Snead said.
"Ideally, whatever measures you take to control sunlight should be adjustable," said Bruce Snead, extension specialist in residential energy at Kansas State University.
This admits sunlight during cold spring periods but shuts it out during a warm fall season.
"Natural shading by trees and vines works best if the plants are tall enough and placed correctly," Snead said.
Solid roofs and overhangs are the best permanent protection against overheating. Overhangs can be designed for the desired shading.
Exterior shades create flexibility, but are hard to mount and vulnerable to weather," Snead said.
Bamboo screens, wood or aluminum slats and woven shade cloth are common materials, usually operated in roll-down systems. While shade paint can be used on glass systems, it is advisable to check with the manufacturer of plastic glazing systems for compatibility with shade paint.
"Interior shades are less effective than exterior shades in blocking solar gain," Snead said.
Cutting nighttime heat loss is possible if there are tight edge seals on insulating materials.
"You can also help cool the space by using natural or mechanical ventilation with your shading system," Snead said.
"Another factor is careful placement of low inlets and high outlets coupled with good prevailing winds," he said. Installation of a fan can also force ventilation to adapt to varying conditions.
"If your existing windows and doors are in poor condition and beyond repair, there are many replacement options," said Bruce Snead, extension specialist in residential energy at Kansas State University.
Doors and windows are the most frequently used items in the exterior shell of your home and their durability, energy efficiency and maintenance are all important concerns.
"In windows, look for good tight construction with integral weather stripping between the sash and frame," Snead said.
Replacement weatherstripping is an advantage, while operating hardware should be very durable. If the windows have steel or aluminum frames, check to see if thermal breaks are used to reduce the possibility of condensation.
"Insulating glass with a low-emissivity coating is recommended in Kansas," Snead said.
Energy efficiency ratings for windows may include both an air infiltration rate and U-value (which is equal to 1 divided by the R-value). These figures are based on laboratory tests of standard units and, in general, a lower figure means a better window.
"Be wary of advertisements that use energy saving claims without providing actual numbers based on standard test procedures," Snead said.
"For replacement doors, a good unit will come prehung for easy installation with integral weatherstripping at the head and jambs and adjustable weatherstripping at the sill," he said.
Steel- or fiberglass-faced doors with foam cores will have higher R-values than solid wood doors, but thermal breaks between the inner and outer skin are essential.
"Most wood contains 40-50% moisture when it is cut, but burns efficiently at 10-20 percent moisture content," Nelson said. "Air-drying the wood over the summer removes most of this moisture."
For optimal drying, split the firewood and stack it off the ground. This allows free airflow throughout the stack. Firewood with moisture content above 20 percent creates several problems.
"Besides poor burning efficiency, excess moisture means excess smoke," Nelson said. "Smoke adds creosote to your flue and chimney, and these deposits are a major fire hazard."