11
REFRIGERATION CIRCUIT
3.1.1 Main components:
Separator:
separates refrigerant liquid from refrigerant gas to protect compressor from liquid hammering.
Electronic expansion valve (EXV):
controls refrigerant flow and reduces refrigerant pressure.
4-way valve:
controls refrigerant flow direction.
Closed in cooling mode and open in heating mode.
When closed, the air side exchanger functions as a condenser and water side exchanger functions as an evaporator.
When open, the air side exchanger functions as an evaporator and water side exchanger functions as a condenser.
High and low pressure switches:
control refrigerant system pressure.
When refrigerant system pressure rises above the upper limit or falls below the lower limit, the high or low pressure
switches turn o, stopping the compressor
Air purge valve:
Automatically removes air from the water circuit.
Pressure relief valve:
prevents excessive water pressure by opening at 3 bar and discharging the water from the water circuit.
Expansion vessel:
Balances the water system pressure. (Expansion vessel volume: 4.8L)
Water flow switch:
Detects the water flow rate to protect the compressor and water pump if the water flow rate is insucient.
Backup electric heater:
Not provided with the standard version (Provided as an option with direct shipping)
Provides additional heating capacity when the heat pump’s heating capacity is insucient due to low outdoor
temperature.
Also protects external water piping from frost.
Water pump:
circulates water in the water circuit.