Roof top unit gas pack. Call for heat the inducer starts and so does the blower motor. The unit will not light off. When power is on the red LED has short single flashes. Not on steady. Call for heat and the LED remains the same short flashes. Legend shows 1 flash is limit switch. Tested the roll out and the limit switch all and both together have continuity when tested at the nine pin connector. Does that indicate a bad control board? Control board that I now have is a 624693 Nordyne.