Management and maintenance of heat pumps
Fouling is always a problem when using heat pumps in fish farming. Plate exchangers with glycol circuits, as mentioned earlier, can therefore be advantageous because they are easier to clean and dis-mantle. Chemical washing circuits should also be installed.
Normally, heat pumps are thermostatically con-trolled to prevent the water freezing and damaging the evaporator. If the temperature falls too low, circulation of refrigerant is stopped allowing any ice that has formed to melt. A back-up heating system might be installed to safeguard against freezing but is expensive. Alternatively the water can be pre-warmed by using another heat source,such as groundwater, before it enters the heat pump.