For each refrigerator, its internal refrigeration dose is certain. If the refrigerant dosage is insufficient, the evaporation pressure will be reduced, the evaporation temperature will be reduced, and the refrigeration capacity of the system will be reduced. If the refrigerant dosage is too much, the evaporation pressure will rise and the evaporation temperature will rise, which will cause the temperature in the box to fall short of the requirements. When the situation is serious, compressor "cylinder punching" phenomenon will also occur.
Therefore, it is necessary to control the refrigerant dosage correctly. When refrigerant is added, if there is quantitative filling equipment, it should be based on the amount of liquid added on the refrigerator nameplate or the instruction manual.
The following methods can also be used to add refrigerants: first, add some refrigerants, and then run for about 20 minutes to observe the frost phenomenon on the surface of the evaporator. If the frosting is not complete, we can add some more, let it work for a period of time, and then take measures according to the frosting situation of the evaporator. If the evaporator surface is frosted and the return pipe surface is frosted, it means that there are too many refrigerants added. At this time, some refrigerants need to be released, and then continue to operate and observe the frosting situation, until the evaporator surface is frosted completely, the return pipe surface is frost-free, only a slight cold feeling can seal the liquid filling pipe mouth, complete the filling work.