The RE590 Ground Source Simulator is designed to provide a limited external heat source for the water evaporator on the R833 Air and Water Heat Pump or R560 Water Water Heat Pump. Normally the R833/R560 is operated from a mains water supply to both the water cooled condenser and the water sourced evaporator. By addition of the RE590, the main water sourced evaporator is replaced by a glycol/water solution pumped around a heat exchanger that is embedded in a 172 litre water or sand/soil reservoir. This is similar to real heat pump installations where the source may be a pond or ground area.
Typically plastic pipes may be buried underground either in long trenches, boreholes or ponds. Usually a secondary fluid, such as a glycol-water mix, is pumped through the pipes where it picks up low grade heat and passes this to the evaporator heat exchanger of a vapour compression heat pump where the heat evaporates the refrigerant. The condenser side of the heat pump then discharges the higher grade heat either to water, or to the building HVAC for heating purposes.
The ground or pond obtains its heat by conduction from the surrounding area and ultimately from the sun warming the above heat exchanger ground area. As may be seen above a potentially large area may be required to make a ground source heat pump a viable proposition. If too small an area is used then the heat extracted from the ground can be greater than that returned by solar gain or local conduction and the result can be freezing of the ground local to the coils of the heat exchanger.
The RE590 Ground Source Simulator allows students to investigate the performance of a limited ground source heat exchanger in a laboratory environment.
