Water-cooling equipment is important for the operation of CO₂ laser tubes. Improper selection of water-cooling equipment will cause the damage on laser tubes, unstable working power, and abnormal laser spots. The requirements of water-cooling equipment selection and installation are shown as follows:

1. Chillers used for 1400T7, 1600S7, 1600F7 (C6),1700H7 (C7),1800W7 (C8) laser tubes shall be able to refrigerate. Optional chillers include CW5000, CW-5200 and DIC004.

Chillers used for 1800U7 (C9), 2000K7 (C20) and other models of laser tubes with high power shall have a better refrigerating efficiency. Optional chillers include CW5300, CW6000 and DIC005.

Chillers of Other models of laser tubes with power under 80W shall be chosen according to their application characteristics. Optional chillers include CW3000, DIC002 or water pumps.

2. If the chiller has no protection function, a protection switch shall be installed at the water inlet of each laser tube. The chiller with protection function can be directly connected to laser tubes. The protection switch or signal wire shall be connected to the power supply of laser tubes to ensure that the power supply can shut down automatically when malfunctions occur in the cooling system.
3. When one chiller is connected to two laser tubes at the same time, if the chiller has only one protection switch, users shall install additional protection switches at the water inlet of each laser. If the chiller has two protection switches at the both water outlets, the protection switches can be used to control the laser tubes directly.
4. User shall not use a chiller with single outlet for 2 laser tubes at the same time. Users shall not use a chiller, except for customized chillers, for 3 or more laser tubes at the same time.
5. Users shall regularly clean the water-cooling equipment and replace the circulating water to prevent the pipe and pump from being blocked.