Thanks to all for your advice. I'm going to troubleshoot this today. We're in Oregon and of course, it't raining (hate rain as I grew up in Seattle!).
Just now, something else occurred which may point me in another direction. The back furnace, which has been on all morning, started blowing cold. It lighted again but it's never done that.
I put a new regulator on my propane tank a few months ago and everything has been operating fine.
I also filled with propane (78 gal tank) a few days ago at a Flying J. The guy filling it used a method I had not seen. He hooked up the hose and turned on the pump. Then he opened and left open the safety valve. He left it open until propane spurted out, then turned off the pump. Is it possible that I have too much LP in the tank with not enough space above it? Just opened the safety a hair and get only vapor. Thanks.
Both furnaces were just working again. I'm thinking this has .got to be a bad regulator or some kind of fuel related issue. Frig is working on propane and range burners light .
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