- Check the temperature, pressure, velocity of the cooling water system and ensures both instruments and water are clean.
- Check the all pipeline routes, including the cooling pipes, all the refrigerating pipes designed for evacuation and drying, hydraulic pipes, cooling pipes, and check for leakage in the convection circulation pipeline.
- Control system: the fuses, thermal protectors, relays, contactors and sensors should be functional, sensitive and reliable.
- Check the readings of the pressure gauge of the refrigeration system, determine that the oil level is within the correct range, as well as ensure color and luster of the refrigeration lubrication oil are correct. Add oil based on the instructions if need be.
- Check the oil level of the vacuum pump, the color and luster of the oil, the noise volume during the operation, and check the vacuum meter readings under the atmosphere. Operate according to instructions if need be.
- Refrigeration box: check the sealing and cleanliness conditions of the sealing strip, the salability of the plate during the rising and falling.
- Heat conduction oil circulation system: observe the heat conduction oil pressure when the circulation pump is working. Observe the surface and the color of the expansion container oil, and the color of the silica gel in dryer.
- Valves: Check the flexibility of all pneumatic valves during opening and closing, repair when necessary. Check the accuracy of vacuum butterfly valve and the effectiveness of all the solenoid valves.
Maintenance of refrigeration system
- Check all cut-off valves (compressor suction valve, exhaust valve, liquid supply valve, hand valves, etc.), make sure all the valves are open and readings are normal.
- Check the compressor running sound when turning the machine on, check the balance of three-phase power if abnormalities occur.
- Check the refrigeration pipe to see if there is any abnormal vibration, if abnormal vibrations exist, corresponding fixing measures can be used.
- Check all operation parameters, identify and fix the problem is abnormalities occur.
- Check the oil cleanliness of compressor and refrigerator on an annual basis.
- Water condensers should be cleaned on regular basis.
Maintenance of vacuum system
- Before turning on the vacuum pump, check whether the vacuum pump oil level is located at about 1/2 of the level glass , if not, add oil.
- Before turning on the vacuum pump, ensure that the back box is dry. If water exists, the temperature of condenser should be turned below -45℃.
- Check whether ultimate vacuum can be achieved in a normal time，observe whether there is noise during the operation of the vacuum pump, check whether there is loosening in the connection between the vacuum oil pump and the pump head. Fix any problems immediately.
- Turn on the vacuum pump valve every week and run for about 2 hours to check whether the pump is leaking or noisy, fix any problems immediately.
- The vacuum pump oil needs to be changed regularly, the prescribed vacuum pump oil must be used, otherwise the performance of the pump will be reduced, or even be damaged.
Maintenance of circulating pump
- Check the running direction of the circulating pump before turning it on
- Check the balance bucket level, circulating pump pressure, heat transfer oil temperature and other parameters, find solutions if problems have occurred.
- Silicone heat transfer oil should be changed once for every five years.
Maintenance of circulating system
- The circuit system should be checked once every 6 months.
- After cutting of the electricity, open the cover plate and use screwdriver to check and tighten the wiring screws in the electrical control box.
- Check internal power line, and wrap up or replace the damaged power line.