Originally Posted by alparmmer
You should have a switch that turns off your water heater. That will shut everything off for you. Bypass the lines, drain the water heater, and fill with pinky.
FYI, not all water heater bypass systems have one valve. Some use 2 valves and a check valve, but the 3 valve system shown below yours is the most common.
The anode, if equipped (Atwood aluminum tank water heaters only have a drain), must be removed to drain the water from the water heater. Inspect the anode for remaining life before re-using it.
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