Causes and troubleshooting of low-temperature water chillers for photoetching machines

The operator of the low-temperature chiller for lithography machine can have a certain understanding of the related faults and solutions during the operation of the equipment, so as to better use the low-temperature chiller for lithography machine. What is the cause of the failure?

1. Refrigerant leakage:
After the refrigerant leaks in the system, the cooling capacity is insufficient, the suction and discharge pressures are low, the evaporator is not covered with frost or there is a small amount of frost at the corners, if the expansion valve hole is adjusted, the suction pressure still does not change much, and the system is balanced after shutdown The pressure is generally lower than the saturation pressure corresponding to the same environment.
Elimination method: After the refrigerant leaks, do not rush to fill the system with refrigerant, but immediately find the leakage point, and then fill the refrigerant after repair.

2. Too much refrigerant is charged after maintenance:
The amount of refrigerant charged in the refrigeration system after maintenance exceeds the capacity of the system, the refrigerant will occupy a certain volume of the condenser, reduce the heat dissipation area, and reduce the cooling effect. The suction and discharge pressures are generally higher than the normal pressure. Value, the evaporator is not frosting, and the lithography machine uses a low temperature chiller to cool down slowly.
Remedy: According to the operating procedure, the excess refrigerant must be discharged from the high shut-off valve after a few minutes of shutdown. At this time, the residual air in the system can also be discharged.

3. There is air in the refrigeration system:
Air in the refrigeration system will reduce the refrigeration efficiency. The prominent phenomenon is that the suction and discharge pressures increase (but the discharge pressure has not exceeded the rated value), and the temperature from the compressor outlet to the condenser inlet increases significantly. Air, exhaust pressure and exhaust temperature all increase.
Remedy: A few minutes after the shutdown, air can be discharged from the high-pressure shut-off valve several times in succession, and some refrigerant can be properly filled according to the actual situation.

4. The frost on the surface of the evaporator is too thick:
The cold storage evaporator used for a long time should be defrosted regularly. If it is not defrosted, the frost layer on the evaporator pipe will become thicker and thicker. When the entire pipe is wrapped into a transparent ice layer, it will seriously affect the heat transfer and cause the lithography machine The temperature of the low-temperature chiller does not fall within the required range.
Remedy: Stop the machine to defrost, and do not hit the frost layer with iron or wooden sticks to prevent damage to the evaporator pipeline.

5. There is refrigerating oil in the evaporator pipeline:
During the refrigeration cycle, some refrigerating oil remains in the evaporator pipeline. After a long period of use, when there is a large amount of residual oil in the evaporator, it will seriously affect the heat transfer effect and cause poor cooling.
Remedy: Remove the refrigerant oil in the evaporator. Remove the evaporator, blow it out, and then dry it.

After the low-temperature chiller for lithography machine has a liquid hammer failure, if the operator or user cannot solve it in time, please contact the manufacturer to solve it.

to sum up
We must clean up and maintain the equipment in time, so as to enhance the life of the equipment.