@Brad your right mate.
I had the same problem on mine and look underneath your van at the water pipes
@Adam G . Look for a cover that is blue and plastic and that's the temperature control valve. Take the blue cover of and adjust the brass nut and problem solved. Hot water will flow at a hotter temp and just be careful not to burn yourself or if you have young ones too let them know that the water will be scalding HOT now
If you can't find it I will take a picture and post it for you if ya like. I had the same problem with my 20.63-1 as well with lack of hot water and I two thought it was the hot water system until I adjusted the temperature control valve.
Good luck
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