The D21-TSSR electronic controller has been designed to be a compact solution that takes full advantage of our patented Air-Flow Sensor which modulates the heater’s capacity according to the quantity of air flowing through the heater by responding to the radiant heat of the eleme...
A pressure differential switch is used to prevent a heater from operating if there is no airflow across the heating elements. The switch is provided with a pitot tube to be installed into the duct, which makes it sensitive to velocity pressure as well as to static pressure. In ap...
A built-in control transformer is required on most heaters to supply 24 volts to the control circuits. A Class II transformer has built-in safety protection and does not require primary fusing. Primary and secondary fuses can be supplied upon request.