that is the expected hook up point. For whatever reason, we get little to no complaints about the winterizing process. Maybe the truck owners are just more resourceful, aren't winterizing or have someone else do it. On small class C's people complained all the time so we have a 3 way valve with "take up" tube.
I hope to add a similar set up going forward on the trucks. Our small C's have an Anderson valve, which handles city water, tank fill and winterizing.
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