So why doesn’t my heater bypass actually bypass the heater ?

[Peteyboy]

My water heater is leaking and until it gets fixed I would like to isolate it from the system as I thought I could do with the bypass option. When I turn the lever to “bypass”, nothing happens,,, water keeps leaking. What am I missing here ?

[Unplanned Tourist]

If you have just one valve for the bypass, water is coming in from the cold side.

To completely isolate the heater, you need two valves. One on input and one on output.

Happy Glamping.

[powercat_ras]

Your public profile says you have a 2015 Itasca 37F. Answer is based upon that ...

Winnebago does not use a full isolation water heater bypass . The single valve is a 3 way valve that re-routes cold water from the hot water heater cold water inlet to a hot water line tee. Between that tee and the hot water heater hot water outlet is a check valve, it is installed into the hot water outlet on the hot water heater.

If the 3 way valve and the check valve are both good you should be be able to have pressure on the cold water line and operate the 3 way valve to bypass. At this point you have pressure on both cold and hot lines in the RV, but only residual pressure in the hot water heater itself.

You should be able to remove pressure using the relief valve and hold it open and get no flow after the water in the HWH drains down to the level of the relief valve if the 3 way valve and check valve are both working right.

[Hikerdogs]

Originally Posted by powercat_ras

Your public profile says you have a 2015 Itasca 37F. Answer is based upon that ...

Winnebago does not use a full isolation water heater bypass . The single valve is a 3 way valve that re-routes cold water from the hot water heater cold water inlet to a hot water line tee. Between that tee and the hot water heater hot water outlet is a check valve, it is installed into the hot water outlet on the hot water heater.

If the 3 way valve and the check valve are both good you should be be able to have pressure on the cold water line and operate the 3 way valve to bypass. At this point you have pressure on both cold and hot lines in the RV, but only residual pressure in the hot water heater itself.

You should be able to remove pressure using the relief valve and hold it open and get no flow after the water in the HWH drains down to the level of the relief valve if the 3 way valve and check valve are both working right.

We currently have the same problem with our 2013 Adventurer 32V. I was able to track it down to the check valve. A new one costs around $25.00 depending on where you get it.

We found the problem when trying to winterize. The weather wouldn't permit leaving the water in the system while we waited for the part so we drained everything and blew air through the system to get out the remainder.

We now have the part, but again it's too cold to lay in the drive and install it. It shouldn't be a big job when the time comes. There's a removable panel at the back of the heater that's accessible from under the coach. The valve screws into the water heater, and the water line also has a threaded fitting. I would guess less than an hour's time, most of it being spent removing the panel (it's screwed and sealed in place), cleaning off the old sealant, and replacing it. Replacing the valve itself "should be" a 15 minute job once the panel is removed.

[Peteyboy]

Thanks all for the info !

[Gary RVRoamer]

The check valve is not closing tightly, as Hikerdogs and Powercat described. That's a very common problem in Winnebago/Itasca coaches of that era. You will want to fix that along with your tank leak.

[powercat_ras]

On my Vista, I removed the check valve that was in the hot water heater outlet and installed a 1/2" gate valve between the hot water heater outlet and the tee. I suggest you consider this rather than just replacing the check valve with another one.

[keymastr]

Did you drain the heater after bypassing it? If not it will still leak until empty.