Despite Their Cool Beginnings, Heat Pumps Face A Hot Future Many People Dislike Heat Pumps, But Because Of Recent Advances They Appear Poised To Capture More Of The Home Heating And Cooling Market.

Posted: January 20, 1991

Paul McGlynn hates heat pumps.

"Every time I walk by a register in cold weather, it seems like it's blowing cold air," said McGlynn, who lives in the Innisfree development in Mount Laurel.

Since fall, McGlynn has been conducting a so-far-unsuccessful campaign to have Public Service Electric & Gas Co. build a gas line to the development so he can heave out his electrically operated pump and buy a gas heating and cooling system.

"I believe they are inefficient and ineffective in the cold months," he said of heat pumps.

McGlynn has lots of company in his dislike of heat pumps, including several Innisfree neighbors who joined him in his campaign, which, according to McGlynn, shows some promise of success by year's end.

But heat pumps also have many supporters and satisfied users. The pumps have been installed in thousands of new homes and apartments in the area, mostly in the last 20 years, and appear destined to capture an increasing share of the home heating and cooling market. Improvements in efficiency, new applications and new designs, and uncertainties in fossil-fuel supplies and costs ensure heat pumps a bright future.

The pumps serve as winter heaters and summer air conditioners. Most are all-electric and require no chimneys or hookups to fuel lines. The air-source pump, the most-common version, extracts heat from outside air in winter and distributes it inside the house, and in summer extracts heat from inside air and takes it outside. A heat pump delivers heated or cooled air to rooms through ducts; other ducts return air to the pump for reheating or recooling.

"Heat pumps are very good systems," said Robert Maguire of Princeton Energy Partners, Yardley, which conducts high-tech energy audits in homes with heating and cooling problems. "How well they operate depends on how they are installed."

"A lot of homeowners don't know how to operate and maintain them," said David Brown, another Princeton Energy Partners auditor in Yardley. "It's not unusual to find them operating without refrigerant - the Freon leaks out. When that happens, the electric backup is operating all the time. They should definitely be checked every year."

In an air-source pump, the backup normally kicks in only when the outside air is too cold to supply extracted heat. The electric backup works like a toaster, heating by electrical resistance or hot wires, and uses much more electrical current than when the pump is in normal operation. A few pumps have a gas or oil backup to eliminate the expensive resistance heat.

Operating costs of heating systems vary widely, depending on the energy efficiency of the systems, the buildings and the comparative prices of fuels, but of the big-three fuels, most experts say gas is cheapest, air-source heat- pump electric somewhat more costly, and oil most expensive.

Jim Reilly, senior applications engineer for Philadelphia Electric Co., which supplies power for thousands of heat pumps in the area as well as gas to many gas heating systems, said the pumps worked best and at lowest cost in newer homes with energy-efficient construction.

More and more new construction meets high-efficiency guidelines, and, according to PE, about 65 percent of homes built in PE's service area are heated with heat pumps.

"We have a very high satisfaction rate in Triple-E homes" that have heat pumps, said Reilly. Triple-E, or EEE, which stands for "excellence in energy efficiency," is a PE-sponsored program in which participating builders apply high energy standards to homes they build and agree to rigid inspections of energy treatments. In typical EEE homes, Reilly said, the estimated costs of heating with heat pumps are actually slightly lower than costs of heating with gas.

"We have heat pumps even where people can get gas, developments where there is a gas main in front but they still have heat pumps," said Reilly. ''I can't say some conversions to gas haven't happened, but I'm not sure of the statistics."

Reilly also believes that poor installations result in most heat-pump problems. "This climate is not at all too cold for heat pumps," he said, disputing a common contention that heat pumps are unsuitable in the Northeast.

In poor installations, Reilly said, return-air ducts often pick up cold air

from unheated spaces instead of returning prewarmed air. That causes the pump to work harder - and use more electricity - to heat the air to a comfortable temperature again. "The duct systems must have integrity," he said.

Correct sizing of the heat pump is also considered critical to efficient operation.

Some heat-pump owners complain that cool air comes from their registers when the pump is supposed to be heating. Typically, the air from heat pumps actually has a temperature of 80 to 90 degrees but feels cool in comparison to the air, often 120 degrees or warmer, produced by fossil-fueled warm-air heaters.

Some heat-pump supporters think that the future of pumps lies in directions other than the ubiquitous air-source pump.

Arthur W. Hunt, president of Jacobsen Energy Industries Inc., of Lansdale, said the answer to better efficiency was in underground water. Jacobsen manufactures geothermal heat pumps that extract heat from water, usually using two wells, one for input and one for discharge.

Hunt said that the well water had a fairly constant temperature of about 55 degrees and that it was a relatively small step up to the 70 degrees needed to heat a home. In the summer air-conditioning phase, heat is extracted from the building and transferred to the water.

"The underlying principle is that the efficiency of anything that has a compressor is proportionate to the temperature difference it is trying to work across," Hunt said.

"With the air-source pump, its efficiency is pretty high when the outside temperature is 47 degrees, but when the outside temperature gets to 30, it is much less efficient," he said. "We can make equipment for any of the methods, but we try to inform people about relative cost, and we always counsel toward the ground-water pump first because it is the most cost- effective."

Hunt said that Jacobsen sold its water-source pumps nationally and that there "are parts of the country where almost every housing development offers water-source pumps either as standard or an option." In northern Indiana, Hunt said, more than 12 percent of new construction is heated and cooled with water-source pumps.

"Around Philadelphia the technology is newer, and until recently we haven't had active support of the electric utilities, partly because they were unaware of the advantages and partly (because of) a wait-and-see attitude," Hunt said. He said water-source pumps typically saved 30 percent to 40 percent of heating costs and about a third of cooling costs when compared with air- source pumps.

Installation costs of water-source pumps typically are considerably higher than for air-source pumps. The "Pennsylvania Heating Systems Manual," published by the Pennsylvania Energy Office, estimates the cost of a water- source installation at $3,800 to $8,000, approximately double that of the $2,000 to $4,000 estimated for air-source installation.

Hunt said his water-source pumps had made gains in the area and were offered as standard equipment or an option at several housing developments, including Timber Knoll at Wood Hill and Taylorville Roads in Washington Crossing.

Dave Knipe, builder of the $525,000-plus custom homes at Timber Knoll, said that about eight homes there had water-source pumps and that the results were so good he had made them standard instead of an option. Knipe said that typical water-source installations cost about $6,000 more than a conventional heat pump but that year-round fuel savings could amount to $1,600. "If you

put your hand across a register, it always feels warm," said Knipe.

A byproduct of the water-source system is that it can reduce domestic hot- water costs by supplying heated water to the home. Most air-source pumps do not heat water, although special pumps for use with water heaters are available. Another advantage, Hunt said, is that there is no outdoor compressor unit of the type used with air-source pumps. Outdoor compressors are sometimes noisy and are regarded as an eyesore by some heat-pump critics.

Jeffrey T. Anspacher, president of USPower Climate Control Inc., of Allentown, thinks it is best to skip water wells and pump the heat directly

from the earth, where temperatures a few feet under the surface generally exceed 40 degrees. USPower makes ground-source heat pumps, which move refrigerant through buried copper coils or systems of pipes.

"Water-source can take much more land area than we do," said Anspacher. ''Also, it's very expensive to drill two wells. Some states are also concerned about the unfiltered water that is being dumped back into those wells. And we're more efficient than they are. I have one in my own home, and year-round heating and cooling costs are $400 to $450."

Other advantages of ground-source, Anspacher said, are "a much higher degree of comfort in both the heating and cooling side, especially when compared to conventional heat pumps. The system also dehumidifies more effectively than a conventional air-conditioning system or a heat pump, which also means more comfort in the home."

No outside compressor is required with a ground-source pump, and the systems can be equipped to heat water for home use.

A number of ground-source pumps have been installed in the area, and they are popular in the Midwest, Anspacher said.

Earth-source pipe systems are generally buried five to six feet and can be placed under driveways or parking lots to minimize space requirements.

Installation cost of a ground-source pump system is estimated at $3,800 to $8,000 in the "Pennsylvania Heating Systems Manual."

Also in development are heat pumps fueled by natural gas, and electric pumps that can operate in off-peak periods and store heating and cooling capacity for release when needed.

Despite the economical operation possible with water-source and ground- source pumps, many experts think air-source pumps will continue to dominate the pump field because of lower installation costs and continued improvements in efficiency.

An example is the HydroTech 2000, a new air-source pump manufactured by Carrier Corp., of Syracuse, N.Y.

The HydroTech, which is featured in a showcase electric house at the National Association of Home Builders' convention in Atlanta through tomorrow, is said to be about 50 percent more efficient than typical air-source heat pumps. One reason for the improved efficiency is three-speed operation.

The HydroTech also supplies domestic hot water, considered an important breakthrough for air-source pumps.

A HydroTech 2000 is also being tested in an area home by Philadelphia Electric, according to Reilly.

"There's no question air-source will remain top dog around here for a long time," he said.


Estimates based on comparable systems used to heat an 1,800-square-foot suburban home over a typical heating season, using current gas and electric rates charged by Philadelphia Electric Co. and an oil price of $1.20 a gallon. Figures for gas and oil heat include cost of electricity for operating fans and pumps.


New construction * $530 $515 $679

Older homes ** $734 $659 $879

EEE homes *** $417 $443 $578

* Energy-efficient home meeting Pennsylvania's Act 222 standards, most built in last five years.

** Homes with no special energy-efficiency treatment.

*** Homes in Philadelphia Electric Co. energy-efficiency program.

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