HEAT PUMP TYPES

Heat pump types describe how the same underlying heat pump technology is implemented using different environmental heat sources. While all heat pumps operate on the same thermodynamic principles, systems are classified according to whether thermal energy is extracted from air, ground, or water.

This page provides a structured overview of the main heat pump types at a classification level. It does not address system selection, efficiency comparison, installation requirements, or application-specific design. Each heat pump type is introduced briefly and linked to a dedicated page that explains the corresponding system configuration in more detail.

This overview builds on the fundamentals explained in Heat Pump Technology.

Air Source Heat Pumps

Air source heat pumps use ambient outdoor air as their environmental heat source. Thermal energy is extracted from the air and upgraded to a usable temperature level for heating or cooling. This category includes systems commonly referred to as air-to-water and air-to-air heat pumps, which differ in how heat is delivered within a building but share the same heat source.

Air source heat pumps are classified as a distinct type because they rely on air as the external thermal reservoir, which varies with outdoor conditions.

LEARN MORE: Air Source Heat Pump

Ground Source Heat Pumps

Ground source heat pumps extract thermal energy from the ground, where temperatures remain relatively stable throughout the year. Heat is transferred from the ground into the heat pump system via ground-coupled collectors or loops. These systems are also known as geothermal or brine-to-water heat pumps.

They are classified separately because the ground acts as the primary environmental heat source, providing different thermal characteristics than air.

LEARN MORE: Ground Source Heat Pump

Water Source Heat Pumps

Water source heat pumps use groundwater or surface water as the environmental heat source. Water is well suited for heat transfer due to its high thermal capacity, making it a distinct category within heat pump systems.

This type is classified based on the use of water as the external heat source and requires appropriate hydraulic integration with the heat pump system.

LEARN MORE: Water Source Heat Pump

Other Ways Heat Pumps Are Classified

In addition to classification by heat source, heat pump systems can also be grouped using other criteria. These classification dimensions are addressed on separate pages to maintain clarity and avoid overlap.

Each of these perspectives describes a different aspect of system configuration rather than a different heat pump technology.