What occurs to superheat and subcooling in a capillary tube system when there is an undercharge?

In a capillary tube system experiencing an undercharge of refrigerant, the behavior of superheat and subcooling is influenced by the limited flow of refrigerant and the changes in evaporator and condenser performance.

When there is an undercharge, the amount of refrigerant entering the evaporator is insufficient to absorb the required amount of heat from the space being cooled. This results in an increase in superheat because the refrigerant vaporizes more completely before it exits the evaporator. The greater the superheat means that the refrigerant is taking on more heat energy as it continues to absorb heat from the environment, indicating that it is getting hotter before it leaves the evaporator.

On the other hand, subcooling is concerned with the cooling of refrigerant in the condenser. If the system is undercharged, the amount of refrigerant available for heat exchange in the condenser is lower, which leads to a decrease in the liquid refrigerant available for subcooling. As a result, the subcooling will decrease due to the lack of sufficient refrigerant to cool down the liquid effectively before it heads toward the expansion device.

Thus, with an undercharged capillary tube system, the correct observation is that the superheat increases while the subcooling