The extremely cold headbox connected with a secondary heat exchanger of a gas furnace has a hole, which can adjust the air flow through the exchanger, a negative pressure channel, a negative pressure port and a pressure switch, an oven, and a manufacturing method. N.

摘要

Box Head cold end coupled to a secondary Heat exchanger of a gas furnace, has a hole for regulating the flow of Air through the Heat exchangerA Channel with a negative pressure Supply Port, a negative pressure Port, input port and the negative Pressure switch; an oven; and associated method.