bypass valve

This system worked fine until this last outing. there is no other valve in the system. I will look in to it this week and see what I can find.
gotta loves this rv thing.

If you can see the back of the water heater. If there is only one valve.And if it used to bypass before, then your valve is either plugged or broken.
Link to single valve

If however this is your first time winterizing , then you might have a second or even third valve in the system.
Three valves

With a three valve you need to shut off the bottom valve (handle perpendicular to the tube)and open the bypass valve(handle parallel to the tube) or no water will flow. This will cause the cold water to flow up the bypass tube to the hot side. At the outlet on top there is either a third valve to keep the water from filling the water heater from the top, or there is a one way check valve at the outlet and only two valves in the system.

Hondavalk wrote:
If you only have one valve on the inlet side then you are shutting off water completely to the hot side. ....

The one valve bypass system will send water to the bypass line and the check valve at the hot water outlet side stops it from going into the water heater. The cold water will travel up the bypass line and flow out the hot water lines and faucets.

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