1.super energy saving 2.Symmetrical room temperature 3.Longer working time 4.Operate easily ... about 12-15 kg/hour.2.Symmetrical room temperature,the whole temperature difference of a standard hen-house 3. ... Fresh air, appropriate temperature in the room,the fan of the wind inlet can ... work steadily for a long time at the temperature of 1450 with our special fire-retardants technic ...