Fuel burner sequencing device with safety checking means

Claim 1

A fuel burner sequencing means for controlling a fuel burner in response to a controller and which includes safety checking means, including: programmed switch means and relay operated switch means; flame sensor and amplifier means controlling a portion of said relay operated switch means in response to a flame at said burner; said burner sequencing means responsive to said controller to provide a normal fuel burner initiation and ignition cycle to establish a flame at said burner with said flame monitored by said flame sensor and amplifier means; and said sequencing means including alternate action safety checking means which includes contact means with a first contact open circuited when a second contact is close circuited; said contact means connected to supply power to said sequencing means in conjunction with said programmed switch means and said relay operated switch means; said safety checking means operating in response to the operation of said controller to power said sequencing means and at the termination of the operation of said sequencing means to reset itself for the next cycle of said sequencing means; said safety checking means operating after said normal burner initiation to immediately stop said sequencing means and turn off fuel to said burner in the event said flame sensor and amplifier means indicates the presence of flame when none should be present, or if flame sensor and amplifier means indicates the absence of flame when a flame should be present.