A burner system for a furnace. The system may have a wedged or other shaped burner box. An air-fuel mixer may be attached to a smaller end of the burner box at virtually any angle relative to a direction of a gas and air mixture leaving the larger box end. A burner head may be attached to the larger end of the box. The burner head may be sufficient for numerous heater sections of a heat exchanger. A spacer and a radiation shield may be situated between the burner head and heat exchanger. An addition of the radiation shield may reduce the operating temperature of the burner box, burner head and/or spacer. A fan may move the gas and air mixture from the mixer, through the box and the burner head. The mixture may be ignited into a flame which is moved into the heat exchanger.