For control of high limit and fan motor in all types of forced air heating systems. Turns fan On and Off according to plenum temperatures. Fan and limit controller with 125 deg. F. fan On and 100 deg.F. fan Off stops. 2000 deg.F. high limit stop. With helical bimetal terminal options available for easy installation. Push-in receptacles for stripped wire. Female receptacles for 1/4" Male flag connectors. Field add-on screw terminals. Controls adapt to many competitive mounting holes in replacement applications. Manual fan switch that overrides fan control to keep fan running continuously.