Taco® Hydro Air Fan Controls Are The used Interface Between The Thermostat And Air Handler.
Fan controls provide advance diagnostic capabilities, universal thermostat compatibility, a simplified wiring layout and automatic multi-speed switching while increasing year round comfort and operating efficiency. Features an isolated end switch to start the boiler and/or pump. Includes 3 built-in fan time delay options, 2 selectable pump exercise modes, a secondary aquastat connection for freeze protection and the ability to switch a pump and/or boiler. 3 Year Limited Warranty.