G&C CCU CO2Y instruction 2016-11-14
4
Evacuation
To avoid inclusion of air or moisture in the refrigerant circuit,
be sure to execute vacuum drying of the entire circuit before
charging refrigerant by using a vacuum pump. Execute
evacuation after securely carrying out airtight/pressure testing.
> When performing vacuum drying, make sure that valve EC1
and EC3 are fully open, please refer to pages 26-27.
Refrigerant Charging
– Calculate the refrigerant charge prior to charging, the system design allows to
a maximum of 3,8L of refrigerant.
– Execute refrigerant charging immediately after evacuation.
– Charge refrigerant R744 (CO2 refrigerant).
– Do not mix with other refrigerant.
– Always use refrigerant grade CO2, moisture content must be below 10 ppm.
Method of Charging
– Close the vacuum valve of the manifold gauge set exclusively for CO2
refrigerant, and separate the vacuum pump.
– To prevent dry ice formation, systems should first be charged with R744
(CO2) vapor to a pressure above the triple point of 4,16 bar.
– Open the joint valve attached to the service piping and Liquid line service
port, and charge liquid state refrigerant.
– Note: Do absolutely not charge liquid refrigerant from the low
pressure side (low pressure service port).
– Avoid overcharging, maximum charging is 3,8 kg
– When the liquid refrigerant no longer goes into the refrigeration unit, close the
liquid line service port and start the refrigeration unit in cooling operation to
adjust refrigerant quantity by charging gas in to the suction line service port.
– After completing refrigerant quantity adjustment, close the refrigerant cylinder
valve and check that the low pressure and high pressure service ports have
been closed.
General startup instructions