The Caframo Ecofan 800 Original; 802 AirPlus and 812 AirMax are heat powered fans designed to circulate the warm air created by a wood-stove operating with normal surface temperatures of between 65°C and 345°C. The optimal running temperature of these wood-stove Ecofans is the same as the recommended safe operating temperature for wood-stoves of between 205°C and 345°C. These fans do not use batteries or mains power.