After the industrial water chiller system has passed the vacuum test, it can use the vacuum state in the system to charge the refrigerant.

Ⅰ. Refrigerant charging of industrial water chiller system

For the newly installed chiller machine, refrigerant can be added from the high-pressure side, and the operation method is as follows:

1. Turn on the cooling water system for the condenser, and the valve in the industrial water chiller system keeps the state during the vacuum test.

2. Connect the steel cylinder with refrigerant with Ф14mm×2mm seamless steel pipe (red copper pipe when filling freon). The mouth of the bottle is inclined downward, and the cylinder is at an angle of 30° with the ground, or the end of the cylinder is raised about 200-300mm.

3. Open the filling valve. When the pressure in the industrial water chiller system reaches a certain level (0.1～0.2 MPa for ammonia system; 0.2～0.3 MPa for freon system), stop charging the refrigerant, and then check the sealing condition of the system at each connection and welding place, if it leaks, you can continue to charge refrigerant.

4. Close the outlet valve on the liquid reservoir and continue to charge the refrigerant. When the cylinder pressure and the pressure in the liquid reservoir reach equilibrium, the outlet valve on the liquid reservoir should be opened.

5. Start the refrigerating machine such as chiller for laser machine to make the refrigerating device enter the operating state while continuing to charge the refrigerant. When white frost appears in the lower part of the cylinder, it means that the liquid refrigerant in the cylinder is almost full. At this time, the cylinder valve and charging valve can be closed, and the bottle can be changed to continue charging.

Ⅱ. Precautions for charging the refrigerant in the industrial water chiller system

1. Unless the external temperature is very low, it is generally not necessary to pour hot water on the cylinder to increase the pressure in the cylinder when charging the refrigerant, because it is not safe to do so. If you need to speed up the filling speed, the hot water temperature must not exceed 50°C, and other methods of heating the cylinder are strictly prohibited.

2. When freon is charged, a filter drier must be installed on the special nozzle to reduce the possibility of water entering the industrial water chiller system. When charging with high pressure section, do not start the compressor, and the exhaust valve must not leak, otherwise liquid hammer will occur.

3. When the refrigerant is charged up to 90% of the charging amount, the charging can be temporarily stopped, and the industrial water chiller system can be tested to check whether the system dosage has met the operation requirements and avoid unnecessary trouble caused by excessive charging. For the old refrigeration system, when the refrigerant needs to be supplemented, it should be charged from the low pressure end