A municipality water reticulation R22 ground-coupled reversible heat pump, was investigated as an alternative to conventional air source systems. The study covers the testing of a heating and cooling system that utilises the ground as its source. The ground source comprises of a municipality water supply line that is modified to allow water to flow through the outdoor coil thus delivering or extracting heat from the system. The investigation was conducted by developing analytical models that were used for the design of a ground-coupled reversible heat pump and a conventional, also reversible air-to-air system. The models were verified with a commercially available computer program as well as with measurements on the two systems. The results show an overall increase in performance with the use of a ground source system over the conventional air source systems. Thus the ground-coupled reversible heat pump system can provide a cost effective alternative to the more conventional air-to-air systems.