Furnace starting method for polycrystalline silicon reduction furnace

The invention provides a furnace starting method for a polycrystalline silicon reduction furnace. The furnace starting method comprises the following steps: mounting a silicon core on a chassis of the polycrystalline silicon reduction furnace; starting a water circulating system of the polycrystalline silicon reduction furnace, and preheating the silicon core; puncturing the silicon core preheated. According to the furnace starting method, before the step that the silicon core is punctured by high voltage, the step that the water circulating system of the polycrystalline silicon reduction furnace is started and the silicon core in the reduction furnace is preheated is added, so that the temperature of the silicon core before being punctured by high voltage can be increased, the electrical resistivity of the silicon core is reduced, further, the puncturing of the silicon core is facilitated, the time required for puncturing the silicon core is shortened, and the possibility that the silicon core topples due to higher brittleness of the silicon core during the puncturing process is further reduced, namely the problem that the polycrystalline silicon reduction furnace in the prior art is likely to topple during the furnace starting process is solved.