About Your Heat Pump; Principles Of Function - Danfoss DHP-H User Manual

2

about your heat pump

2 .1

Principles of function

A heat pump utilises the energy found in a natural heat source. Simply put, it obtains energy
in the form of heat from a heat source. The heat pump is, therefore, a very environmentally
friendly and economical way of heating a house.
The heat pump has three separate fluid circuits
• Heat transfer fluid circuit – is the circuit that contains the water that transports the heat/
energy to the heating system and the water heater.
• refrigerant circuit – is the circuit that contains a chlorine and freon free refrigerant that
inside the heat pump, transfers the energy retrieved from the brine circuit through evapo-
ration, compression and condensation, and supplies it to the heat transfer fluid circuit.
• Brine circuit – is the circuit that contains an antifreeze water based mix that obtains and trans-
ports energy from the heat source to the heat pump. This circuit is also known as the collector.
Expansion valve/
pressure drop
Enclosed
refrigerant
1 A fluid (brine) filled hose is lowered into a lake, buried in the ground or lowered into bedrock. The
brine obtains energy from the heat source by the fluid temperature in the hose being heated a few
degrees by the surrounding heat source. The fluid filled hose is also known as a collector.
2 The brine is guided into the heat pump's evaporator. The enclosed refrigerant in the
refrigerant circuit is forced to boil as the pressure in the expansion valve drops and
later evaporates to a gas in the evaporator. The energy produced during this process is
released by the slightly heated brine.
 The refrigerant that now contains a large quantity of energy in the form of heat is trans-
ferred to the compressor, which both increases its temperature and pressure.
 The refrigerant then continues to the condenser. When condensing, the refrigerant
supplies its heat energy to the heat transfer fluid circuit. The refrigerant's temperature
decreases and returns to a liquid state.
Danfoss – 
Condenser
Evaporator
Brine
Figure 1: Function principles of a heat pump .
VUBMA102
Heat transfer fluid
circuit
Compressor/
Refrigerant circuit
pressure increasing
Brine circuit