Installation function
An air/water heat pump installation uses the outdoor air to heat up a
home. The conversion of the outdoor air’s energy into residential heating
occurs in three different circuits. From the outdoor air, (1) , free heat
energy is retrieved and transported to the heat pump. The heat pump
increases the retrieved heat’s low temperature to a high temperature in
the refrigerant circuit, (2) . The heat is distributed around the building in
the heating medium circuit, (3) .
Outdoor air
The outdoor air is sucked into the heat pump.
A
The fan then routes the air to the heat pump’s evaporator. Here, the air
releases the heating energy to the refrigerant and the air's temperature
drops. The cold air is then blown out of the heat pump.
B
Refrigerant circuit
A gas circulates in a closed system in the heat pump, a refrigerant, which
also passes the evaporator. The refrigerant has a very low boiling point.
In the evaporator the refrigerant receives the heat energy from the out-
door air and starts to boil.
C
The gas that is produced during boiling is routed into an electrically
powered compressor. When the gas is compressed, the pressure in-
creases and the gas's temperature increases considerably, from 0 °C to
approx 80 °C.
D
From the compressor, the gas is forced into a heat exchanger, condenser,
where it releases heat energy to the electric boiler/indoor module,
whereupon the gas cools and condenses into a liquid again.
E
As the pressure is still high, the refrigerant can pass an expansion valve,
where the pressure drops so that the refrigerant returns to its original
temperature. The refrigerant has now completed a full cycle. It is routed
to the evaporator again and the process is repeated.
F
Heat medium circuit
The heat energy that the refrigerant produces in the condenser is re-
trieved by the indoor module's water, the heating medium, which is
heated to 55 °C (supply temperature).
G
The heating medium circulates in a closed system and transports the
heated water's heat energy to the house radiators/heating coils.
H
The electric boiler/indoor module’s integrated hot water coil is located
in the boiler section. The hot boiler water heats the hot water.
I
The temperatures are only examples and may vary between different installations and
time of year.
11
Chapter 2 | The heating installation – the heart of the house
NIBE VVM 225
