Qualifying Criteria for
Ground Source Heat Pumps

Ground source heat pumps must meet Canada's Energy Efficiency Regulations before they can qualify for the ENERGY STAR® symbol in Canada.


Ground Source Heat Pump – It uses the thermal energy of the ground or groundwater as the heat source and heat sink for residential space heating and/or cooling. It may provide both space heating and cooling, cooling-only or heating-only functions. A ground source heat pump model consists of one or more factory-made assemblies that normally include an indoor conditioning coil with a means of moving air, compressor(s) and refrigerant to fluid heat exchanger(s). In addition, some or all of the domestic water heating shall be provided through the use of a desuperheater, integrated demand water heater or a separately installed compressor that provides demand water heating. The ground source heat pump includes all the equipment and connections from the point at which the ground heat exchanger enters the house, except for indoor equipment that was installed by someone not representing the manufacturer or manufacturer's representative such as the ground heat exchanger installer.

Closed Loop System – A ground heat exchanger in which the heat transfer fluid is contained in a closed system.

Open Loop System – A ground heat exchanger in which the heat transfer fluid is part of a larger environment. The most common open loop systems use ground water or surface water as the heat transfer medium.

Direct Expansion (DX) – A ground source heat pump system in which the refrigerant is circulated in pipes buried in the ground, rather than using a heat transfer fluid, such as water or antifreeze solution, in a separate closed loop and fluid to refrigerant heat exchanger. A DX system includes all of the equipment both inside and outside the house. DX systems may be single-speed or multi-speed.

Integrated Demand Water Heating – This term is used to describe ground source heat pumps that include a water heating function in the refrigeration cycle. Integrated demand water heating differs from a desuperheater in that the integrated demand water heating model provides all or nearly all of the domestic hot water needs and provides hot water even when space conditioning is not required. This includes systems that employ the use of a separate water heating compressor unit or that use the same conditioning and water heating. It is also sometimes referred to as full-demand or demand water heating.

Coefficient of Performance (COP) – A measure of efficiency in the heating mode that represents the ratio of total heating capacity to electrical energy input.

Energy Efficiency Ratio (EER) – A measure of efficiency in the cooling mode that represents the ratio of total cooling capacity to electrical energy input. For DX systems, the EER will be calculated in accordance with CSA Standard C748-94 Performance of Direct Expansion (DX) Ground Source Heat Pump conditions.

Test Standard

CAN/CSA 13256-1

Technical Criteria

Table 1: Key Product Criteria for ENERGY STAR Qualified
Ground Source Heat Pump

Product Type EER COP Water Heating (WH)
Closed Loop 14.1 3.3 Yes
With Integrated WH 14.1 3.3 N/A
Open Loop 16.2 3.6 Yes
With Integrated WH 16.2 3.6 N/A
DX 15.0 3.5 Yes
With Integrated WH 15.0 3.5 N/A