With the middle valve open and the other two closed, you bypass the water heater for winterizing (so you don't have to fill the water heater with RV antifreeze.)
With the middle valve closed and the other two open, water flows through the water heater for normal use.
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— David
Zero Gravitas — 2017 Flying Cloud 26U | WBCCI# 15566
He has all of the virtues I dislike and none of the vices I admire. — Sir Winston Churchill
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