Captn Sharpie
I have three valves inboard of my water heater:  one for cold water supply, one for hot water outlet, and a third connecting the two lines.  Last winter I closed all.  This summer I left them all in the "open" position (see photo).  The hot water from the faucets was inconsistent - cold, then hot, then cold again.  I suspect the middle valve is my by-pass system and should be in the closed position so the two supplies do not mix.  The answer might be obvious, just looking for confirmation.  Thanks.  (from a 2014 177). IMG_1205.JPG 
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mikes
[image] 
Mike
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the5reeds
The theory is that in winter, you can fill your water pipes with potable antifreeze, but not in the hot water tank. so the bypass valve setup allows water to bypass the tank. Personally I prefer to drain the lines and tank and using a compressed air supply, blow the water out of the lines, both hot and cold and drain the hot water tank. Cheaper and pretty easy to do.  
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Carl Bragiel
Very fortunate placement of the circuit board! Mine happens to be loose and buried between the water heater and furnace... as far away from the access panel as possible. Fact is, I need to get to it and looks like it isn't going to happen easily.
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SandyC

Where IS  the water heater?My 189 R didn’t come with a diagram.

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Tom
Walk around the outside and find the exhaust/access grill. The tank is buried under something on the other side. Under dinnette seat is common.
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