Gebwell Qi 10, Installation, Operation And Maintenance Manual

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3 GROUND SOURCE HEAT
AND COOLING
A well-designed and appropriately dimensioned ground
source heating system is affordable in terms of operating
expenses and energy efficient. With a ground source heat
pump, you can efficiently heat both interior air and
domestic water. In summer, the system can also be used
to cool interior air in an environmentally friendly fashion.
3.1 Ground source heat energy
A ground source heat pump collects heat from the ground
and transfers it inside the building. The heat can be
collected using pipes sunk in a bored well, heat collection
pipes installed near the ground surface or pipes anchored
at the bottom of a water system.
Bored well as a heat source
Ground as a heat source
Water system as a heat source
More information on heat collection systems and their
scaling can be found on the website of Gebwell Ltd. and
the Finnish Heat Pump Association.
www.gebwell.com
www.sulpu.fi
3.2 Ground source cooling
The cold temperature of the brine can also be used to cool
dwellings. In summer, the free cooling energy can be
transferred from the ground with just a circulation pump.
The ground source heat system can be connected to the
convection heaters of the ventilation system or a
underfloor heating/cooling system for cooling purposes.
3.3 Ground source heat pump’s operating
principle
The ground source heat pump’s refrigerant circuit
includes four main components:
•
Evaporator
•
Compressor
• Condenser
•
Expansion valve
The heat in the ground is absorbed into a liquid solution
circulating in the heat collection pipes.
In the evaporator, the liquid comes into contact with the
refrigerant that, when vaporised, binds heat energy from
the liquid solution that circulates in the ground. The liquid
solution returns to the ground about 4°C cooler than when
coming out to the surface. The lowest permissible
temperature for the liquid solution coming to the heat
pump is -5°C.
The compressor increases the pressure and temperature of
the refrigerant. The refrigerant also absorbs the heat
energy generated by the compressor’s operation.