Air conditioning a house is the costliest part of owning it. Though this has always been the case, rising energy costs mean that an efficient system is more important than ever. The fight to conserve energy took a giant leap forward earlier this year when a new seasonal energy-efficiency rating (SEER) standard for residential central air conditioners took effect. As of January, the minimum efficiency rating manufacturers are allowed to produce is 13. So what exactly does this mean?

Rick Roetken, director of marketing for residential and light commercial systems at Farmington, Conn.–based Carrier Corp., explains it this way: SEER is measured in BTUs of cooling per watt of electricity, so a 21 SEER product, for example, will yield 21 BTUs of cooling per watt of electricity. An average home will need 30,000 BTUs of air-conditioning power per hour, he notes. “Needing to achieve 30,000 BTUs per hour of operation adds up quickly with older models at 10 SEER or lower.”

The new standard is good news for home buyers. “SEER is a measure of a product's energy consumption taking into account the normal cycling of the product,” explains Roetken. “The measure is much like miles per gallon in a car.” So a higher rating means homeowners can heat and cool their houses for a lot less money.

The January time frame applies only to units manufactured after that date. Dealers and distributors may still sell existing units with ratings less than 13, and builders may still offer them in their houses. Strangely enough, builders—who are normally slow to change—have been ahead of the curve in adjusting to the new standard, says Bill McCullough, director for cooling products at Richardson, Texas–based Lennox International. “The first adopters were some of the national builders,” he says. “We were pleased to see that happen.”

In addition to the new energy-efficiency ratings, manufacturers must also get ready for a new refrigerant rule that takes effect in a few years. After Jan. 1, 2010, manufacturers will be required to eliminate ozone-depleting R-22 and switch over to more environmentally friendly R-410A. “The phaseout of the refrigerant has to be gradual,” says Don Wood, national builder accounts manager for Tyler, Texas–based Trane. “There is a schedule, and we have to maintain that schedule.”

Air-conditioning units with R-410A refrigerant cost more money, and 13 SEER systems cost more than lower-rated units (the better the performance, the higher the price). Manufacturers will not say how much more 13 SEER units cost, but they admit that a unit with the new refrigerant is likely to be about 5 percent to 10 percent more than comparable products.

It is important, then, to convince home buyers that purchasing the most up-to-date HVAC system is the smartest and perhaps most economical decision, despite the increased cost. For one thing, buying the lower SEER product will result in higher utility costs.

Additionally, an R-22 unit will end up costing more in the long run. “After January 2010, [home buyers] will not find R-22 systems available for purchase as manufacturers must discontinue R-22 production,” Roetken says. “Homeowners who operate systems with R-22 refrigerant are much more likely to experience increases in service costs over the life of their product.” Because R-22 will be available in limited quantities, home buyers will experience the normal effects of supply and demand, he says. “Literally millions of systems operate on R-22 refrigerant, meaning demand will remain high until those products reach the end of their service life,” Roetken says. “Supply, on the other hand, is substantially limited.”

McCullough offers advice on how builders should reassure home buyers that the extra cost is worth it: “I would tell them to sell their buyers on comfort and pay-back,” he says. “Tell them don't just look at price. They should look at resale value as well. High efficiency sells.”

PURE ON: The manufacturer says Infinity System is the first to use a single control to integrate and manage temperature, humidity, airflow, ventilation, indoor air quality, and zoning. It also provides longer heating and cooling cycles at lower fan speeds for energy savings and consistent temperatures, the maker says. It has an automated diagnostic feature that monitors the system, a variable-speed fan, and a non-ozone-depleting Puron refrigerant. Carrier Corp. 800-227-7437.

HIGH EFFICIENCY: The SEER 19.50 XL19i line of air conditioners and heat pumps has one of the highest energy-efficiency ratings on the market. The unit features dual compressors, a variable speed outdoor fan motor, and an all-aluminum spine fin coil that provides low airflow resistance, greater heat exchanging capabilities, and more resistance to corrosion and leaks, the company says. Trane. 903-581-3033.

SMALL TIME: This 13 SEER [mc]2 air conditioner is the smallest 13 SEER air-conditioning system in the industry, its manufacturer says. It is available in 1- to 3-ton sizes and is ideal for applications where space is limited. The unit has an aluminum-tube coil, and a polymer mesh and coated steel coil guard protect the condensing coils. Luxaire Corp. 405-364-4040.

SPLIT UP: The ultraquiet and compact 13 SEER high-efficiency unitary split air-conditioning systems range from 1.5 to 5 tons and are sized for slab or rooftop mounting in single or multifamily homes. The units have some of the smallest footprints in the industry, the company says, so they are economical to transport and install. Each unit features a factory-installed liquid line filter dryer and copper-tube, aluminum-fin coil construction. Fedders Corp. 908-604-8686.

For more product information, visit ebuild, Hanley Wood's interactive product catalog, at or