Ruud UGUC-89EAGR Gas Furnace (1989)
Furnace ignites and goes out. In less than a minute it ignites again and goes out. Symptoms include clicking noises and slight gas smell. A technician fixed the exact same symptoms about ten years ago by replacing a component on the furnace itself. I can't remember which component. Someone suggested that it might have been either the round pressure switch or the Honeywell S86F intermittent Pilot box. Any ideas are appreciated.