Superheat Calculator

How it works: Superheat = suction line temperature − suction saturation temperature. Read the saturation temperature off your gauge’s P–T scale (or a refrigerant P–T chart) for your refrigerant and measured suction pressure. As a general guide, most systems run roughly 8–20°F of superheat at the evaporator — but always follow the manufacturer’s target and charging method (e.g., the superheat method for fixed-orifice systems). Low superheat risks liquid floodback; high superheat suggests an undercharge or restriction.