Originally Posted by Poohbill
From my reading, the bypass valve was so the antifreeze poured into the drains didn't get into the HW tank. I just can't see how it could.
The bypass is to prevent filling the HW tank when you winterize with RV antifreeze. The HW tank should be drained for winterizing by removing the anode rod (good time to examine the anode for wear) and opening the relief valve to drain rapidly. Open your low point drains (should be a note on the side of the TT where they are located). The bypass valves are located on the back side of the WH tank.
If you don't know how to winterize a RPod I suggest you look at any of several You Tube videos on the subject and they should tell you how it is done.