Analysis of the cause of excessive suction temperature of compressor The high suction temperature is mainly due to the increase of superheat of suction. Note that high suction temperature does not mean high suction pressure, because the suction is superheated steam. Under normal circumstances, the compressor cylinder head should be half cold and half hot. If the suction temperature is too high, the cylinder head will all heat up. If the intake temperature is higher than normal, the exhaust temperature will increase accordingly. The main reason for the high suction temperature:
1. Insufficient refrigerant charge in the system. Even if the expansion valve is opened to the maximum, there will be no change in the amount of liquid supplied, so that the refrigerant vapor is overheated in the evaporator and the suction temperature is increased. 2. The opening degree of the expansion valve is too small. As a result, the circulation amount of refrigerant in the system is insufficient, the amount of refrigerant entering the evaporator is small, the superheat is large, and the suction temperature is high. 3. Expansion valve screen is clogged. The amount of liquid supplied in the evaporator is insufficient, the amount of refrigerant liquid is reduced, and a part of the evaporator is occupied by superheated steam, so the suction temperature increases. 4. The suction temperature is too high due to other reasons. If the heat insulation of the return air pipe is not good or the pipe is too long, it can cause the suction temperature to be too high
