What does high pressure in conjunction with low superheat (SH) and high suction (SC) indicate?

High pressure combined with low superheat and high suction typically indicates that there is an overcharged system. When a system is overcharged, the excess refrigerant leads to an increase in pressure within the system.

The presence of low superheat suggests that the refrigerant is not absorbing enough heat as it passes through the evaporator, which usually indicates that there is too much refrigerant in the unit. High suction pressure reinforces this observation, as it shows that the refrigerant maintaining a liquid state in the evaporator is not allowing for adequate vaporization and thus proper heat exchange.

Therefore, this combination of parameters—high pressure, low superheat, and high suction—directly points to the excess quantity of refrigerant, confirming that the system is overcharged.