[Working principle] The thermoelectric module in the fireplace fan acts as a small generator to drive the fan motor, so no battery or power is required for the drive/operation of the fireplace fan. The fireplace fan is placed on the fireplace rack, which uses the temperature/heat energy on the fireplace rack to electricity and drive the fireplace fan. The rotation speed of the fan depends on the combustion temperature in the fireplace frame. The higher the furnace temperature [Product structure] Aluminum radiator, thermoelectric module, bimetal heat conduction sheet, wind blade. When the furnace temperature is low enough to extinguish the fire, the rotation speed of the fireplace fan will slow down until it stops. Normal operating temperature 50 ° C to 350 ° C. [Safety design] The support and base of the fireplace fan are treated with anodized aluminum, which can withstand high temperature up to 752 ° F (400 ° C), and will not deform or change color even if it works under high temperature for a long time. [Environmental protection and energy conservation] The improved hot circulation of high-temperature self generation can bring greater comfort, and the wood used in the stove can be reduced by about 28%. [Longer service life] The fan base is equipped with a bimetal safety device. If the surface temperature exceeds 250 ° C, the safety device will gently lift the front of the fan to protect the TEG and motor.