Hello, on my furnace over the last two years I have had the gas pressure checked, the service line checked for moisture, replaced the regulator valve, replaced the thermostat, replaced the fan limit control switch, and replaced the 3 wire pilot burner. Problem was worse but seems to have gotten better (at least it starts). Now the thermostat calls for heat I hear a click, then I see the spark taking place on the ignitor, after a short time the valve clicks and the flames come on. After a while just when I think the fan should come on the gas shuts down. A little while later it goes through the same sequence but I hear a lot clicking noise (kind of like loud static but I see not sparks other than at the ignitor but that is not were the noise is coming from) the process starts again and then the next time the furnace works. Any ideas what is wrong here? What I shoud replace or check?

We had this problem several times over the years with our old gas furnace and each time it was the ignitor. We now have installed a high efficiency furnace. The constant repair calls throughout the winter were getting too much.

Tick