Test Operation & Troubleshooting & Maintenance 
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It is the heart of the cooling system, mainly used to turn the 
low-temperature, low-pressure refrigerant vapor to 
high-temperature high-pressure vapor and then discharge it to 
the evaporator. The two-stage enthalpy-adding compressor is 
adopted herein, which can improve the heating performance of 
the unit largely.
 
Electrostatic 
Expansion Valve
 
It is one of four main components and used to turn the 
hi-pressure liquid refrigerant to low-temperature, low-pressure 
vapor-liquid mixture and adjust the refrigerant flow rate entering 
the evaporator.
 
It is installed at the side of the suction line, and used to 
prevent liquid refrigerant entering the compressor, which if not 
avoided will lead to wet compression or even liquid slugging. 
 
It is used the switch flow direction of refrigerant and then 
realize switchover between cooling and heating. It also can be 
used for defrosting through the counterflow.
 
It is the water-refrigerant plate type heat exchanger, used to 
liquefy the high-temperature high-pressure vapor refrigerant or 
evaporate the low-temperature low pressure liquid refrigerant. 
Heat of condensation is taken away by circulation water and 
heat for evaporation is supplied also by circulation water.
 
It is the power equipment for water circulation.