How do i hook up a thermostat to just turn on the blower on my furnace.?

low voltage system. i have a supplemental heating system running hot water through a coil in the furnace. i want to hook up the blower to come on when it calls for heat, and leave the main thermostat hooked up as is for emergency backup. thanksHow do i hook up a thermostat to just turn on the blower on my furnace.?You would need a new thermostat for the hot water coil, when that reaches a certain temperature have it start the blower. If you are using the low voltage you would need the 24 volts to activate a solenoid which would run the 110 to the fan motor.How do i hook up a thermostat to just turn on the blower on my furnace.?Add a switch to the fan and disconnect it from the thermostat that way you can turn it on any time you want.How do i hook up a thermostat to just turn on the blower on my furnace.?How Many Wires on old Thermostat? You need at least 3 . If You Have that many or more Buy a Heating %26amp; cooling Thermostat And follow Direction's That Come with It.