In this article, we will define both superheat and total superheat, calculate total superheat, explain how to use total superheat to check the refrigerant charge, and show where the measurement points are taken on an air conditioning system. Total Superheat Formula: Actual Vapor Line Temp – Sat Temp = Total Superheat So what does this mean and what is the difference between Superheat and Total Superheat? Simply put, superheat is the increase in temperature of the vapor refrigerant. On a split s