Replacing Hot Water ByPass Valve

That is why I ask how you knew the bypass was bad and suggested the check valve.

Glad you got it fixed.. I have a 3-valve system, no check valve.

Another issue I do not have.... I read about folks who use the cut off valve on the shower head (or another they installed as I did) to conserve water in the shower complaining about how it's all cold when they restore flow.

Same valve is the cause I suspect. At very low flow rates there is not enough pressure to open the valve, so the line from the mixing valve to the shower head.. Fills with cold water only.

Well the problem turned out to be anti-syphon valve on the water heater, took it off and cleaned it out. It was full of calcium buildup.
Everything is working great now.
One more thing to put in the book of knowledge
Thanks to all for their input and suggestions

L

Try cleaning the aireator on each faucet. They could be full of sediment from the water heater. I think you said that you were in the Arizona area before your trip and there is very hard water there causing sediment in the tank. also there is an attachment type yellow wand which you use to clean out the water heater tank by inserting in the drain hole and attaching it to a water hose. You will be surprised at the amount of sediment that will come out. First just unscrew the aireator on each faucet and run the hot water water without it to see if clogged. Chuck

Unscrew it pull the Spring and check valve stopper out and screw it back in place. When You get to the place that has one in stock replace it!
Or just leave the guts out leave it alone and Blow the lines clear when winterising!

This is what I know so far

On the outside of the coach the hot water release valve let's hot
water out as it is suppose too.

Then the bypass valve when in the hot water position will not let water
flow, if you move it alittle bit towards the bypass it will let water flow, but only cold water.

How do you know the valve is shot?

From your use of the singular, I gather you have a 3-way valve (one) in the cold water line and nothing but a "T" fitting in the hot line.. Two possible issues.

1: You are getting only warm water and thus assuming the bypass valve is letting cold water bypass.... Suggestion: Check the outside shower to make sure you have not left the mixing valves open and cut off flow at the head (Iniside shower too for that matter)

2: no how water flow: This is USUALLY the fault of the outlet check valve, not the bypass vavle.. It is harder to replace.. (Some folks have been unable to remove it from some heaters)

One "young lady" I know simply pulled the guts out of it using needle nose pliers.. Worked great since she winterizes by the dry method (Air not pink stuff).

She fixed it later.... (Bought a new trailer)

Had similar situation and was the hot water check valve or backflow valve located either on heater or in line near heater. See if you can talk Paramount RV into working on it today. If it is the by pass ask them for the same service. We live in Sparks when we are home. Call me if you need further info. Chuck 775 742 2476.

If you have easy access to it, it is an easy job..You probably have PEX water lines. Go to Home Depot, Lowe's into the plumbing section and get SharkBite fittings.
They will have everything you need to cut out the old valve and replace it. No special tools needed.

cut and cap the bypass lines with some sharkbite caps for now enjoy your trip put the bypass in before you winterize the camper.