Definition

Water loop air heat pumps (WLHP) are a type of HVAC system that uses a water loop to transfer heat between different parts of a building or multiple buildings. They consist of several electrical water-to-air heat pumps connected to a common hydronic distribution system.
The individual heat pumps extract heat from the water loop during heating mode and reject heat into the water loop during cooling mode.

The water source can be a closed loop of water that circulates within the building, exchanging heat with the ground (geothermal) or through an additional device (cooling tower, dry cooler, etc). It can be also an open loop like a lake or river as a heat source or sink.

Collection details

Recently launched in 2025, data collections are organised annually.

The data provides information on the country, capacity in kW, type of unit, type of configuration, type of compressor, type of refrigerant, both in number of units and amount in euro.