It is known that if the volume and pressure of the refrigerant of the same quality are changed, the temperature will have different performance, that is, if the liquid refrigerant absorbs more heat, the refrigerant of the same quality will exhibit higher pressure, temperature, and volume. With less heat, the pressure, temperature, and volume will be lower.
That is to say, if the return air temperature of the compressor is low, it will generally show a low return air pressure and a high amount of refrigerant of the same volume. The root cause of this situation is that the refrigerant flowing through the evaporator cannot fully absorb itself and expand to a predetermined pressure. The heat required for the temperature value causes the temperature, pressure and volume of the return air to be relatively low.
There are two causes of this problem:
1. The liquid refrigerant supply of the throttle valve is normal but the evaporator cannot absorb heat and supply the refrigerant to expand normally.
2. The evaporator works normally but the throttle valve refrigerant supply is too much, that is, the refrigerant flow is too much. We usually understand that there is too much fluorine, which means that too much fluorine will also cause low pressure.