The standard type of geothermal heat pump is a packaged unit. The entire refrigerant circuit, including both heat exchanger coils (water-to-refrigerant/source and air-to-refrigerant/load), is inside one cabinet. The unit is entirely assembled and charged at the factory, so that no on-site refrigerant or brazing work will need to be done. This is the most common type of geothermal heat pump installed.
Split system geothermal heat pumps are separated into two sections: the compressor and the water-to-refrigerant heat exchanger in one cabinet, and the blower assembly and air-to-refrigerant heat exchanger in either an air handler cabinet, or in a fossil fuel furnace. The refrigerant circuits of these components must be connected on-site with brazed copper refrigerant tubing, and then charged with refrigerant.
Split systems have a much shorter life, on average, than packaged geothermal heat pumps. Split systems are much more prone to contamination during assembly than packaged units are. It is more difficult, and requires more skill, to braze and charge a refrigerant circuit at a home site than at a factory. Any contamination of the refrigerant circuit causes compressor burn-out and system failure. For this reason, we don't recommend that our customers install split system geothermal heat pumps.