Lennox 57W68 Natural Gas Orifice 44

The Lennox 57W68 is an orifice for natural gas, or a small device used in Lennox gas furnaces. It is a disc of an exact size that is mounted into the furnace’s gas burner assembly. Through the adjustment of the orifice that controls the amount of natural gas that is supplied to the burner, the flame intensity of the burner and in extension the heat produced by the furnace is determined. A large orifice diameter admits more gas inflow hence raising the flame intensity in the process of heating. On the other hand, a smaller opening of the Polytec allows partial restricting of the gas flow for a lower flame intensity and less heat production.