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Yes. In the 1997 legislative session, Kansas law makers adopted the American Society of Heating, Refrigerating, and Air-Conditioning Engineers Standard 90.1 as the commercial building energy standard.
"This standard addresses the design of the building envelope, lighting and power distribution systems, heating and air conditioning systems, and most other energy features of the building inch," said Gene Meyer, extension mechanical engineer at Kansas State University. "The standard applies to all commercial buildings designed for human occupancy. Industrial buildings are not covered by this standard."
The legislature also required the builders of new homes to tell the potential buyer whether the home meets the Council of American Building Code Officials (CABO) Model Energy Code. The CABO Model Energy Code balances insulation levels, window types and sizes, and equipment performance to help assure an energy efficient home.
"Rather than specifying the home meets the Model Energy Code, the builder has the option of providing the buyer with a long list of energy-influencing features of the home, levels of insulation, window type, equipment efficiencies, and other features are included in this list," Meyer said.
No.
"The primary reason is that placing an air filter at this location destroys the air delivery characteristics of the supply register," said Doug Walter, president of Kansas Building Science Institute, Manhattan.
Forced air supply registers are designed to "throw" the air into the room so that it achieves a mixing action with the air already in the room. Good circulation is essential to a system that operates comfortably and efficiently.
"All filtering of the air should be done before the air enters the furnace or air handling unit," Walter said. "This keeps the furnace heat exchanger and air conditioning coil clean. Placing filters on both the return and supply sides of the system could reduce air flow to the point that the furnace or air conditioner could be damaged."
If you need more effective filtering of the air in your house, consider adding a high-efficiency particulate air (HEPA) filter or electrostatic air cleaner to the return side of your ducting system, or purchase a free-standing unit that can run continuously.
"Radon levels can be reduced in almost any home to below the Environmental Protection Agency's (EPA) guideline of 4 picocuries per liter ," said Bruce Snead, extension specialist in residential energy at Kansas State University.
"The average U.S. home has an estimated radon level of 1.3 picocuries per liter (pCi/l)," Snead said. "The EPA suggests action be taken to reduce the level if it is greater than 4.0 pCi/l. Levels of 25 pCi/l have been found in some Kansas homes and one home in four has the potential for elevated radon levels according to the statewide survey of 1987-88."
The most effective method to permanently reduce radon is to install a sub-slab ventilation system, consisting of a 3-4 inch plastic pipe inserted through a hole drilled in the basement floor. The pipe is routed up through the house to a fan located in the attic or outside, and from there the exhaust is vented above the roof line. The fan runs continuously to create a suction under the basement floor.
"This creates negative air pressure below the basement floor, causing the radon gas to be drawn off by the fan and vented to the outside," Snead said. "This method may cost several hundred to several thousand dollars or more and should be done only by a contractor experienced in radon mitigation."
Additional measures which can contribute to reducing radon levels include supplying make-up air for air-consuming appliances such as furnaces, boilers, water heaters, and clothes dryers to reduce house suction on the soil and caulking and sealing large cracks, gaps, and penetrations in basement walls and floors.
"Cover and seal open sumps and replace stand type pumps with submersible types," Snead said. "Cover any open soil with heavy plastic."
A "ton" is the measure of the cooling capacity of an air conditioning unit. "It is an indication of the rate by which the unit removes heat from a building," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
One ton of air conditioning removes 12,000 British thermal units (Btu) of heat an hour. "The term was derived from the time when ice was used for refrigeration," Hayter said. "One ton of air conditioner cooling capacity removes the same amount of heat required to melt 2,000 pounds, or one ton, of ice in 24 hours."
Typically, residential central air conditioners will range in capacity from 1 1/2 to four tons. Window units will many times be rated in Btu per hour. For example, a 6,000 Btu/hr. window unit would have the capacity of one half ton.
"There are few add-on devices for air conditioners that effectively reduce energy costs while maintaining cooling capacity," said Dennis Matteson, extension specialist in small business energy at Kansas State University. "Evaporative precoolers, are effective in decreasing maintenance, operating, and cooling costs."
Precoolers are water pads that cool air entering the condenser unit by means of evaporation.
The condenser unit is located outside, and during hot weather the efficiency of the air conditioner decreases when the air entering the condenser increases. Cooling air before it enters the condenser increases efficiency.
"These units have been used extensively for large refrigeration systems and are becoming more common for smaller units," Matteson said.
"An earth-tube system should be only a supplemental source of cooling for your home," said Bruce Snead, extension specialist in residential energy at Kansas State University. "For Kansas, a recirculating system is most appropriate."
This system uses a fan to circulate air from the house through pipes buried in the ground and back into the house.
"It avoids using outdoor air, which may have a higher humidity and temperature than indoor air," Snead said. "It also eliminates the problems of dust and insects entering the system."
Using interior air also requires less of a temperature drop from the system.
Tube diameters should be from four to 12 inches. The larger diameters are preferred because they have greater surface area and allow more air flow.
Tube lengths should be from 25 to 50 feet, and pipe material should be low-pressure, solid plastic with sealed joints.
"Multiple tubes provide more cooling and should be set up in parallel, with a minimum separation of two feet, " Snead said. "Both tube joints and penetrations in the foundation should be sealed to prevent water leakage and possible entrance of radon gas."
The deeper the system is located in the ground, the better. Lay the tube away from the house so it is surrounded by as much soil as possible. The supply and return tubes should be well separated, both in the ground and in the house.
"The temperature drop occurring in a typical system should be from five to 15 degrees Fahrenheit, " Snead said.
Fans should be sized for each system. The most effective is 200 to 400 cubic feet per minute (cfm) for each tube. Four- to eight-inch diameter tubes should be in the 200 to 300 cfm range; eight- to 12-inch diameter tubes from 300 to 400 cfm.
"Do not expect an earth-tube system to air condition your home completely," Snead said. "The best system is a simple one that takes advantage of any necessary excavation and uses low-cost materials. An expensive and elaborate design is not appropriate."