I have had the same trouble with my Modine HD60 as D45 mentioned. I discovered it about a year after it was installed. I pinched it just like the post above and it worked fine for another year and the upper limit switch started to trip again. I removed the upper most burner tube and welded that...
Funny you say that, I looked at the welder and was going to do just that but the metal is fairly thick so it should stay crimped together. After I assembled it and fired it up I realized I should have did the same thing to the lower part of the bottom tube as well but that one is far enough from...
The soot was only a result of the flame being allowed to creep up the slot in the tube of which I merely pinched it off with a pair of Vise grips. Now the entire flame is directed straight into the heat chamber. I posted the pics containing the soot just to show how close the flame was coming...
Phil I think that flame you see rolling out in the 2nd picture was causing enough heat to trip the upper limit switch. I took a before and after video I sure wish I could post them.
I tried to find an earlier post, I know many have had and are probably still having the issue of their heater blowing cold air due to the upper flame rollout switch tripping.
I had the repair tech over on 2 occasions but the problem still not fixed. I decided to take another look myself before...
Chalk up another flame rollout trip here too. It's time for Modine and similar manufacturers to fix this problem permanently, I've been reading forum posts that are dating back to 2006. I've been waiting for a repairman now for over a week and decided to look at my unit to see what the heck is...