1. The evaporator outlet should use the thermometer to […]
1. The evaporator outlet should use the thermometer to measure the temperature or look at the suction pressure to check the superheat;
2. The expansion valve adjusts the superheat degree to be too small (the liquid supply amount is too large), and the adjustment rod should rotate half a turn or one turn in the clockwise direction (that is, increase the spring force and reduce the valve opening degree) to reduce the refrigerant flow rate; The number of turns of the thread at one time should not be too much (the adjustment rod thread rotates one turn, and the degree of superheat changes by about 1-2°).
3. Expansion valve adjustment experience: Turn the adjustment rod thread to change the opening degree of the valve, so that the evaporator can just be frosted or dew condensation outside the return pipe. For a refrigerating device with an evaporation temperature lower than 0 degrees, if it is touched by hand after frosting, there is a feeling of coldness that sticks the hand, and the opening degree is appropriate; for the evaporation temperature above 0 degrees, the condensation is visible. Judgment of the situation.
4. The correct debugging of the expansion valve directly affects the cooling effect and energy saving of the cold storage. The cooling of the cold storage is slow, and the expansion valve is improperly adjusted. According to the thermal properties of the refrigerant, the lower the pressure, the lower the corresponding temperature; the higher the pressure, the higher the corresponding temperature. The adjustment of the expansion valve is the most critical. The opening degree of the expansion valve is small, the flow rate of the refrigerant is small, and the pressure is low; the opening degree of the expansion valve is large, the flow rate of the refrigerant is high, and the pressure is high.