Product Review

Refrigeration Calculating guide to back and head pressures. For use with R12, R134a, R22, R123, R404a, R407c, R410a, R507, and R508b. On the front of the guide is a sliding chart to calculate back pressure, air temperature and head pressure for specific suction temperatures and condenser temperatures. This guide is simple to use and takes the guess work out of checking proper charge of a system. On the back side is a color chart for start, run and common wires on specific models of compressors. Also on the back is a thermostat control setting chart for different types of equipment and a guide for evaporator temperatures. This item is made of thick cardboard stock with metal corner rivets and is 7.25 inches long by 3.5 inches wide.