The actual unit size should be within 15 percent of the calculated load. Heat pumps that are too large waste energy and do not provide proper humidity control. Residential system design is straight-forward, but the most satisfactory results are obtained with experienced contractors. It may be advantageous to specify two-speed or variable speed systems where heating requirements are much greater than cooling, to assure good humidity control. Finally, the contractor should examine ways to use the GeoExchange system to provide hot water.
Proper installation is a key to success.
The GHPC recommends that consumers employ experienced contractors who will provide the names of customers with comparable systems. For larger commercial systems, design professionals should aid in the selection of qualified bidders to assure quality installations at competitive prices. In both cases, local utility and manufacturer members of the GHPC may be able to assist. In addition, many states have Heat Pump Councils which may provide additional referrals. No existing space conditioning technology offers greater comfort, economy, or environmental compatibility than the GeoExchange heating and cooling systems now available for residential and commercial installations.