So I apologize to the forum. I never updated the post. So I went to my local RV repair shop. They were certain it was one of two issues.
1) Failed over limit switch. The unit has a switch that if the unit get too hot, it'll shut it down to prevent any problems. Well, sometimes it does not reset...so then you have a different problem. New switch $15.
2) Failed gas flow igniter switch (not it's technical term). I think it's around #4 or #5 on Mike's timeline. New switch $15.
The third items it could have been is the sail switch on the fresh air. Mike's #3. I could visually inspect that when the fan started, the sail switch moved into position from the outside air flow. Personally, I think it was the over limit switch failure. It was working when it died. So I think it got too hot and shut itself down. The switch never reset.
So the parts are relatively inexpensive. However the shop told me that the labor was going to be the real issue. Supposedly, they need to remove the unit to get to where they need to replace these switches. My memory is a little foggy from some brown water after I picked up the Pod from the shop to try and forget the part at the end where I laid down the plastic. But the heater works like a dream now.
Sorry for the delay. I still need to post the pics of my 179 head sink removal. We are so happy without it.
Thanks
Jeff