Hearthstone 90-57210 Wood Stove Blower Kit for Heritage, Castleton, Tribute, Man. Genuine Hearthstone wood stove blower kit for select models. Must be used in conjunction with the accessory rear heat shield (Heritage 8021 – PN 90-68210) (Tribute 8040 – PN 90-68400) for mounting and in order to force the heated air forward over the stove’s top. Replacement For Part Number. Instructions for Hearthstone Wood Stove Room Air Blower Kit: 90-57210. A snap switch located on the top of the blower housing activates the blower. It will take several minutes for the heat of the stove to activate the snap switch. A rheostat controls the blower fan speed. The rheostat knob is located on the right hand side of the blower housing. Turn the knob clockwise to the on position. The fan is on the highest setting when it is first turned on. By continuing to turn the knob clockwise the fan movement will be reduced until it reaches its lowest setting. If the fan does not operate at the lowest setting, the rheostat will require adjustment. Contact your dealer for rheostat adjustment. To turn the blower off, turn the knob fully counterclockwise until it clicks into the off setting. Listing and template services provided by inkFrog.