However, with winter approaching the Meilleurs decided to take action. "We simply could not make it through another cold season with out current unit," Meilleur said. "We contacted our local utility, OGE Electric Services, for assistance."
To the Meilleur's surprise, they learned about a very efficient and affordable system: the next generation in geothermal heat pump technology which represented a 50-65% savings in their heating and cooling costs.
The existing ductwork was found to be in good condition and was utilized with the "EarthLinked" unit from ECR Technologies Inc., Lakeland, Fla.
Drilling for the four, 100 foot loops utilized by the three ton system was initiated and finalized within one day. Drillers finished excavation for the earth loops, inserted the loops and backfilled the area while the installed removed the old equipment. ECR replaced the old central air conditioner and electric furnace with an enclosed compressor unit one half its size and relocated it in the homeowners' garage. The ECR unit produces very little noise, much like the hum of a household refrigerator.
"Geoexchange systems have been around for quite some time, but have been expensive to install¿ until now," said Morris Lovett, PE, senior engineer with OGE.
ECR's system, for instance, has lowered installation costs by eliminating the plastic ground loop, water circulating pump and intermediate heat exchanger common in similar systems. Its copper refrigerant tube earth loops are inserted in small bore holes or trenches to directly extract heat energy from the earth. The miniaturized system and smaller earth loops can be installed with less time and expense.
ECR's Joe Parsons said the start-up procedure is extremely simple compared to other heat pumps. "Our charging procedure requires only a look at the sight glass to determine if the refrigerant charge is correct." Liquid refrigerant is added to the active charge control at approximately six pounds per ton of capacity. When the liquid refrigerant reaches a visible level in the active charge control, the charge is correct. No charging chart is necessary.