Only Cold Water from Hot Water Faucets

[capeApe]

Hi guys. I have a 1995 RoadTrek popular 190 Chevy. Issue: Cold water from hot water faucets. Yes water tank heats up. Yes bypass in correct position. I am way past all that.

I am having the most peculiar hot water problem. I started diagnosing and I noticed the cold water line was going into top of hot water tank.

I fixed that by reversing the lines, and also replaced the by-pass valve kit as they were allowing water to get past the stop valve no matter what position it was in. Still no hot water from faucets. (yes bypass is in correct position)


On hot water tank, I disconnected top water line (with bypass on until I was ready), and the hot water tank was still full, and I turned on pump, and then opened bypass valve to allow hot water from tank to flow out from top valve.

I was definitely getting good flow and nice hot water from the top output. But when I connect the plumbing line, I cannot get hot water from the faucets. Only Cold.

HOWEVER, when the pump was turned off, there was still enough pressure in the tank from being hot to push some water out, and the water from sink faucet was HOT only with the pump off (from sink faucet) and turned instantly cold when I flicked the pump on.



It's the weirdest thing. Someone mentioned a "mixing valve", or maybe there is another check valve down the line that it not allowing more hot water through when the pump is running and the cold water is somehow overriding it? Addition: There is an end-point faucet that was installed with a very expensive in-line water filtration system

:danger:Symptom: Cold water flows from hot sink faucet with 1 bypass valve in "bypass" and 1 valve in "tank".
:danger:Symptom: Some hot water from hot water faucet when pump is OFF and hot water faucet open.
:danger:Symptom: Cold water from hot water faucet with pump ON.


I've asked on a few facebook groups so far with no luck and it's been 10 days troubleshooting this issue! Please help! ��



Thanks in advance for your time.

 

[jrobe-ClassB]

I am no plumber but there has to be cold water bypassing your water heater. I assume that your RV water line diagram is like the one in this link. If your pump is on and there is only cold water coming out the faucet, the cold water is bypassing your water heater. The only place that that could happen on my RV and in this typical water line diagram below would be at that white bypass hose. I don't think those hose valves are blocking water flow through the bypass but maybe I am missing something unusual on your RV. Let us know how you fixed it.

https://www.rv-insight.com/RV-Plumbing.html

 

[The Eyesore]

In your third picture, the bottom valve is closed (redirected). There's no way for the water to flow, in that configuration. Both valves need to be open.

 

[capeApe]

In your third picture, the bottom valve is closed (redirected). There's no way for the water to flow, in that configuration. Both valves need to be open.

Yes. I’m thoroughly familiar with how the valves work. I was trying different combinations for diagnosing the problem. So that’s just how they were when I took the photo. They are brand new

 

[ChicagoTom]

Then you valve is screwed up. What else could it be?

 

[capeApe]

Omg! I was able to contact previous owner. He said that rhe outdoor shower faucet was leaking at the hot water tap, so instead of replacing it, he cut the plumbing and bypassed hot water tank which messed up the plumbing big time !! Nice to know when I bought it !!