I am also having the IF issue. I took everything apart today to a take a look and everything looks fine with no spider webs. I did not take of the the jets to look at them when I had the burner tube off so I will need to do that tomorrow. Mine starts up with all the clicking and I can see the flame through the window for about 2 to 3 seconds and then it goes out so I know I am getting some kind of flame. My heater is less than 1 year old. How can I check the flame sensor? It has been raining very heavily here and the insulation inside where the burner tubes go is soaking wet, could this be causing the problem? There are no leaks what so ever when it's not raining so i don't think that I have a leak. I am going to order a cover to prevent the inside from getting soaked in case that that's what is causing the problem. Any help is appreciated.