The Model FW-5B is equipped with a precision air regulator which enables the process controller output to the heatgun heater element control circuit only if an adequate air source is connected. The process controller is potentiometer controlled, from several LOW thru HIGH settings. Heatgun air temperature is controlled by turning the knob clockwise for higher air temperatures.

The control box is equipped with two separate switches, where the HEAT switch will not work unless the MAIN POWER switch is enabled. Note that the MAIN POWER switch is also an overcurrent protection device.