Many thanks John for all of your work on this. Yes, I saw the regulator in the manual diagram but dometic told me there was no regulator in the system! I don't think the CS rep actually knew. But the problem in all of this is that there is no gas flow at all at the stove at 5500 feet. None, not even a hint. Yet at the nearby outside camp stove fitting there is gas. Back at lower elevation it works fine. Why? The main regulator at the tank is not influenced by elevation. Not positive but fairly certain the "obstruction" is at the stove "regulator". But why. This will be checked more thoroughly. All other appliances work fine (though furnace now shows a sail switch issue on the board read out). Now, that original part that is called a "regulator pipe" has now been superseded by a new dometic part that has the "regulator" integral to the entire burner assembly. With no help or sympathy from Dometic, I have one of these assemblies coming. Dometic would not supply it because it is a gas part. But I could buy it on line from an RV parts supplier! BTW, great pic of the R60 regulator. I was also told 4500 feet was the limit. Ill report any findings. the old regulator is going to be disassembled.