Premix boiler construction

In a boiler having a sealed combustion chamber and means for supplying a premixed air and gas mixture containing sufficient air for combustion of the gas, an improved burner construction comprising:

• a burner element extending into the combustion chamber and having a substantially conical wall tapering from a base end to a tip end which presents an aperture;
• a plurality of ports in said wall for passage of the mixture therethrough into the combustion chamber for combustion therein, said ports being arranged in a plurality of separate clusters each separated from other clusters and each including a plurality of individual ports;
• a distributor core disposed within said burner element and having a substantially conical wall spaced inwardly from the wall of the burner element, said wall of the burner element tapering from an open base end which forms an inlet for receiving the incoming mixture to a tip end which presents an aperture;
• and
• a plurality of spaced apart openings in said wall of the distributor core for passsing the mixture to said ports of the burner element while effecting a pressure drop across the wall of the distributor core.