the heater bypass valve is under the bed, lift the foot of the bed up and the pipes are there (as well as some of the electrical stuff), 3 valves - cold and hot close, bypass 0pen.
The drain valves for the water tank are the low-point drains in the water bay, if I recall properly - pull the rings out to open the low-point drains.
I think that's correct, I only had mine for about a year and a half.
2020 Winnebago View 24D
2018 Jeep (JL) Wrangler