How heat pumps work

In Nature, heat energy always moves naturally from hotter to colder areas (that’s the Thermodynamic principle).

Whereas heat pumps work transferring heat from a colder area (source) to a warmer area, by using electrical energy and exploiting the physical characteristics of refrigerant fluids.

A refrigerant fluid, by changing its status (from liquid to gas and vice-versa), absorbs or releases energy. Heat pumps technology exploits this physical feature by manipulating the refrigerant pressure though four main devices components:

1. In the evaporator the refrigerant in liquid form evaporates, absorbing heat from the source (for example from the external air).
2. The compressor increases the refrigerant pressure
3. In the condenser the refrigerant in the form of gas liquefies releasing heat to the user (for example the fan-coil hydraulic circuit)
4. The refrigerant is led through an expansion valve, which lowers the pressure, allowing the refrigerant to be looped again to the evaporator.

Then, in winter season you can remove heat from a cold external source, and transfer it to the indoor heating system, in summer, by reversing the unit, you can absorb heat from the building and rejecting it outside. That’s the typical functioning of Swegon reversible chillers & heat pumps.