I have A 2008 Coachman Mirada and it has a one valve water system. I understand it enough to use the r v, just was all messed up when I winterized and hope to find instructions before that happens again.
Let me give a shot never had one but understand the principal. The hot connection iis a one way valve right on the heater .
At the bottom is a 3 connection valve. In position A valve handle facing heater allows water to enter heater and blocks bypass line. In position B valve lines uo with bypass line and away from heater this stops water from entering htr and allow flow thru bypass line to isolate. Check valve will prevent water from entering above!
The bypass valve does the work of all three former valves in the back of the HW tank. In my unit, I then drain the HW tank, shut off the fresh water tank and stick the antifreeze hose into the antifreeze container. very nice system, but the back of the tank has hoses running everwhere
the class A coachmen Mirada has the water works panel. I have no valves on the hot water tank. I have seen the rear of it. The one valve the rv has is in the city water and Sewer tank connection door on the other side of the rv. It may be defective from what ive read. but a rare bird it is.
If you're winterizing by blow-out of the lines, the quick way to check the valve position is the leave the water-heater pressure relief valve open as you turn the air on. If air hisses out of the PRV, go turn the by-pass valve until it doesn't.
Doing it once a year, I find I can't remember where the valve handle has to go, so this method works every time!
__________________
Frank and Eileen
No longer RVers or FR owners
Perhaps a diagram I found will help. The valve is set in the operating mode...to bypass, the valve would be in the vertical position. Only one 3 way valve is needed as there's a check valve on the hot water discharge preventing water flow into the tank.
Linear Mode
