Precautions for changing the refrigerant oil

Timely and correct replacement of refrigeration oil, not only can make the best performance of the machine, but also is conducive to the service life of the machine. Many customers have reflected with Hualai: due to the replacement of counterfeit or fake refrigeration oil or the failure to replace it in time, the machine is damaged. It is reminded that you must go to the regular company to buy the refrigeration oil, and pay attention to the correct model and timely change Change the question. There are several situations when changing the refrigerant oil:

(1) Replace the refrigerant oil without internal cleaning:

The compressor performs pump collection action, recovers the system refrigerant to the condenser side (note that the minimum suction pressure of pump collection action is not less than 0.5kg/cm2g), removes the refrigerant in the compressor, retains some internal pressure as the power source, and discharges the refrigerant oil from the oil drain angle valve of the compressor. After the refrigerant oil is removed, the angle valve can be closed. At this time, the suction of vacuum pump can be used to pump the new refrigerant oil from the drain valve to the compressor through the conduit. After the standard oil filling amount is reached, the drain valve will be closed and the vacuum will continue to reach the standard requirements, i.e. the oil change operation will be completed. This can prevent air leakage of the system from causing difficulties in subsequent operation. It is recommended to select high (low) pressure side angle valve or other relative high-level point for the contact point of vacuum pump to prevent the vacuum pump from being damaged by pumping refrigerant oil.

(2) Replace the refrigerant oil and clean the inside:



The action of oil discharge is as mentioned before. After the refrigerant oil is removed and the internal and external pressure of the compressor is balanced, use the Allen wrench to loosen the flange bolt, remove the oil filter joint and the flange for cleaning the hole (or the flange of the oil level switch), and then compress it Remove the pollutants in the oil tank, check whether the oil filter mesh is damaged, blow out the sludge and pollutants on it, or replace the oil filter with a new one. Pay attention to the tightening of the filter interface nut when replacing, and make a good sealing to prevent internal leakage; the inner gasket of the oil filter connector must be replaced to prevent internal leakage; other flange gaskets are also recommended to be renewed.



4. Precautions for refrigerant oil replacement:

(1) Different brands of refrigeration oil must not be mixed, especially mineral oil and synthetic ester oil must not be mixed.

(2) If the refrigeration oil of different brands is replaced, the remaining original refrigeration oil in the system shall be removed.

(3) Some oil products are hygroscopic, so do not expose the refrigeration oil to the air for a long time. During installation, the exposure time shall be shortened as much as possible, and vacuumizing operation shall be done well.

(4) If the compressor motor is burnt out in the system, special attention shall be paid to remove the remaining acid in the system when replacing the new machine, and check the acidity of the refrigeration oil after 72 hours of commissioning and operation. It is recommended to replace the refrigeration oil and drying filter to reduce the possibility of acid corrosion. After that, the refrigeration oil shall be tested or replaced again about one month after operation.

(5) In case of any water inflow accident in the system, special attention shall be paid to the removal of water. In addition to the replacement of refrigeration oil, special attention shall be paid to the detection of the acidity of oil products, and the replacement of new oil and dry filter shall be carried out in time