How does a heat pump work?

A heat pump is an economical alternative to a traditional boiler. In fact, the technology produces up to 75% of the heat you need. The remaining 25% comes from natural gas or electricity. 

The operation of a heat pump is simple:

• heat energy is extracted from the environment (water, air, soil)
• which is then released as heat into the heating system connected to the heat pump.

A distinction is made between different types of heat pumps, depending on the heat source used and that which needs to be heated (water or air).

Download the infographic (in French)

Step 1: Extracting heat from a heat source

A heat pump extracts heat from a heat source (soil, air, groundwater) with the help of collectors.

A coolant transports this energy to a compressor. The advantage of the coolant is that it boils at a low temperature and evaporates.

Step 2: From the heat pump to the heating system

In the heat pump compressor, these vapours are compressed until they reach a higher temperature than the air or water used to heat the home.
The compressor is the only part of the heat pump that uses energy (electricity or natural gas).

This heated vapour then ends up in a condenser. Here the vapour transfers its heat to the heating system of the house.

Step 3: The cycle starts again

An expansion valve lowers the pressure of the vapour and cools it down again to a liquid. It is then sent back outside to evaporate, after which the whole process can start again.

Properties of a heat pump

• It is comparable in size to a classic floor-standing boiler.
• It is also available in hybrid versions combining a boiler and heat pump.
• The hybrid version always uses the most economical function.
• It operates at a low temperature regime. This requires a well insulated home and a heat release system that operates at a low-temperature.