Maintenance sequence of screw chiller

Maintenance sequence of screw chiller

1、 Routine maintenance.

Make sure to start and shut down the machine according to the specified procedures every day, and record the operating parameters at certain intervals. Clean the refrigeration and cooling water filters 24 hours after the unit starts to operate. Check the evaporator and condenser pressure of the unit through the pressure gauge display of the control cabinet to see the difference between the evaporation temperature and the chilled water outlet temperature, and the difference between the condensation temperature and the cooling water outlet temperature. In addition, pay attention to check the refrigerant filter dryer. If there is frost at the outlet of the drying filter, it indicates that there is blockage. Replace the refrigerant filter dryer in time. Check whether the oil level in the oil tank changes. If there is a large drop, add refrigerant oil in time.

2、 Regular maintenance.

Regular maintenance includes weekly, monthly, quarterly, semi annual and annual maintenance.

Check and analyze the operation parameter record table every week.

Check whether the fastening bolts of the power supply wiring are loose every month, and check whether all moving parts have noise, whether they operate normally, whether the high and low pressure values of the refrigeration system are normal, whether the operating current of each motor and the insulation resistance of the unit are normal, whether the drying filter and the mirror are normal, and clean the filter screen. If the mirror shows humidity (the color turns red), replace the filter core.

Quarterly maintenance is to check the temperature drop of refrigerant when it passes through the refrigerant dryer under the condition of full load operation of the unit on a monthly basis.

The semi annual maintenance is based on the above, and the physical and chemical analysis of the refrigerant oil should also be carried out to determine the water content and acidity of the refrigerant in the unit, and all possible loose electrical connectors of the control cabinet, starting cabinet and motor should be tightened and checked.

The annual maintenance is based on the previous series of operations. If the refrigerant oil has been emulsified, the refrigerant oil of the same brand and model should be replaced. Replace the refrigerant oil filter if necessary. At least once a year, disconnect the connecting pipe at the outlet of the safety valve, carefully check the valve body to see if there is corrosion, rust, scaling, leakage and other phenomena inside. If there is corrosion or leakage, replace the safety valve. This inspection should be carried out by maintenance personnel.