This HearthStone fan blower includes a heat sensor that will automatically activate the blower when the stove heats up. It may take several minutes for the stove to be hot enough before the blower is activated, and the blower will automatically turn off should the wood stove cool down. You can also adjust the fan blower speed with the included rheostat fan control. The rheostat is located on the right side of the blower. Friendly Fires recommends that all wood stove fan blowers be kept on low for reduced noise and fan longevity (similar to fan use in your car heater).Requires Rear Heatshield