Abstract: A burn rate control valve for gas fired heaters in the form of a 1/4 turn ball valve having two flow passages through the valve member in which one flow passage is for full gas flow and the other flow passage is smaller in diameter for low gas flow in order to provide a full burn rate or a low burn rate. The two passages are dimensioned and angularly related such that the larger or full burn rate passage essentially provides unrestricted flow when aligned with related ports or piping with the smaller or low burn rate passage being angularly related to the larger passage at an angle less than 90.degree. in order to maintain a flow passageway when the ball valve member is moved to a position with the larger passage perpendicular to the associated ports. This angular relation assures that the smaller flow passage will be opened before the larger flow passage closes too much in order that the burner will not cease to operate and not provide a lower burn rate than intended.

Abstract: An ignition device for burners in which an ignition spark is established over a nonconducting surface between a hot electrode and a grounded electrode or electrically conductor portion which enables a greater spark distance to be obtained as compared to an ignition spark which jumps across an air gap between two conducting electrodes. An additional feature of the present invention is the provision of a high limit control positioned proximal the burner such that flame resulting from heater inlet blockage will flash upstream into the vicinity of the high limit control to control operation of the burner.