Since I finished installing a second fresh water tank under the seat storage, I decided to install a winterizing hose and hotwater tank bypass; so it will be easier when it comes time to winterize the Scamp
with RV Antifreeze. The hot water tank already had one shut off valve on the lower 1/2" pex pipe. So, I added a second shut off valve on the upper 1/2" pex pipe, then installed a bypass between the two pipes using two brass tee's with another shut off valve in the middle. When time to winterize I can close the upper and lower vlaves and open the center valve; keeping the RV Antifreeze from going into the water heater, allowing it to bypass the water heater and still access all other hot water water lines.
This is the way most bigger rv's set up the water heater bypass for winterizing. Then next to the fresh water tank I installed a 1/2" plastic Spiral Tee fitting in the hose between the fresh water tank and the water pump. I installed a shut off valve on the water tank side of the plastic T -valve; to close off the fresh water tank side when adding RV Antifreeze.
Then I added a 5' clear hose with a shut off valve on the Spiral Tee fitting to draw the RV Antifreeze into the pipes with the water pump.
So, when it's time for winter and I want to winterize. I (1) close upper and lower water tank valves. (2) Open middle water tank bypass valve. (3) Close valve between Spiral Tee and fresh water tank. (4) Open valve to Antifreeze clear hose; put clear hose into a gallon jug of RV Antifreeze. (5) Turn on water pump. (6) Open kitchen and shower hot and cold falcets until pink antifreeze comes out. Flush toliet until pink antifreeze comes out. Always allowing pink anitifreeze to drain into sink and shower drains. (7) Last of all drain water heater.
Winterizing the unit will take approximately one gallon of RV Antifreeze and take less then ten minutes to do.