Heat pump types

The operating principle of all heat pumps is identical. The heat pump type depends on the choice of pumping energy source (air or water).

a. Air - Water Heat pumps. The air pumps on water pumping energy exploit the surrounding air. The thermal medium is water that circulates in the heating or cooling system (underfloor pipes, panels, old type radiators, fan coils) or in a storage tank’s exchanger with integrated heat pump (for DHW).  They are ideal for any kind of houses and workplaces as they operate at high but also low ambient temperatures that can reach -20 ° C.

b. Air - Air Heat pumps. This type of pumps exploits the surrounding air and attaches heating or cooling through air. In the first case, it exploits the ambient air (as source of energy) and in the second case, it uses the indoor air or a combination of indoor and ambient air offering simultaneously room ventilation.

c1. Water - Water Heat pumps (closed circuit geothermal pump). This category of heat pumps exploits the heat from the ground with horizontal or vertical exchangers which transfer the heat of the subsoil to the pump. In this case, the thermal medium is still the water as in the case of air-water heat pump.

c2. Water - Water Heat Pumps (open circuit geothermal pump). This type exploits thermal energy of groundwater with the appropriate drilling operations. This pump has the same function with the previous type, except that the materials that are used in the primary circuit are suitable for open circuit. This type has the highest performance coefficient (COP).

The choice of the most suitable type of heat pump (air, water, ground) is customer and application driven in order to achieve optimum operating levels and secure the highest possible heating-cooling performance with the lowest possible cost.  

Additional types and special characteristics of heat pumps:

Air-water heat pumps are divided into two sub-categories:

a. Heat Pumps contain all the needed equipment to operate in a sole device (monoblock or compact heat pumps) and are installed outdoors, in order to exploit directly the energy of the surrounding air. However, there are some models that are connected with air ducts and can be installed indoors.

b. Heat pumps (split), have two devices that are installed both indoors and outdoors. In this type of heat pumps the cooler, that exploit the energy from the surrounding air, is placed in the outdoor (exterior) device, while the indoor (interior) device contains all the hydraulic (mostly wall mounted) connections.  

Another distinction of heat pumps is the following:

a. Heat pumps with DC inverter technology are continuously adapted to the requirements of cooling or heating and as a result the operating consumption is remarkably reduced.

b. Heat pumps on/off which perform to the maximum without being continuously self-adapted to the demands of the heated room, as in the previous heat pump type.

Some types of heat pumps: