That's what I thought, Flirty. Thanks for the photo to confirm it though.
If you are sure there is plenty of heat with the inlet blocked (there is a possibility that the propane valve itself is not opening fully), I would be looking at the main board.
I am not a repair dude, I try to figure out the most likely fault; then pull the LRU (Line Replaceable Unit); and replace it.
See if that fixed the problem.
A certified technicial would figure it out immediately and fix it. It would most likely cost more if you both guessed right, but would be a lot less if you guessed wrong.
(Don't Ask Me How I Know - DAMHIK)
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
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