Only warm water from water heater

[Pthornburg10]

I have a 2023 cougar 25rds with a tankless water heater. I recently had a light winterization done where they blew out all lines and added antifreeze to pee traps. We are now on a trip and noticed, that after hooking everything up as we usually do, that the hot water isn't as hot as it normally is. I'm talking just more that luke warm and we have the temp turned up to 124. It's nothing like before. Am I missing something? Is there a bypass valve somewhere? I've checked propane and the power button on the water heater. Those are ok.

[RV Vacation]

Originally Posted by Pthornburg10

I have a 2023 cougar 25rds with a tankless water heater. I recently had a light winterization done where they blew out all lines and added antifreeze to pee traps. We are now on a trip and noticed, that after hooking everything up as we usually do, that the hot water isn't as hot as it normally is. I'm talking just more that luke warm and we have the temp turned up to 124. It's nothing like before. Am I missing something? Is there a bypass valve somewhere? I've checked propane and the power button on the water heater. Those are ok.

The bypass is a good question. Most newer RVs do have a bypass but usually found on a tank type hot water heaters so as not to fill the tank with antifreeze.

Click the link below for some ideas regarding bypass valves. Your symptoms certainly sound like that could be your problem.

https://rv101withmarkpolk.com/2019/1...%20or%20closed.



A second link to tankless water heaters you may find useful.

https://www.monkeywrenchplumbers.com...%20hot%20water.

[Cheesehead4Life]

In addition to the above, make sure the outdoor shower valves are off. If open that can cause the hot and cold water to mix in the lines.

[ChuckS]

I am guessing your On Demand WH is the Girard GSHW-2....

Many folks are not up to speed on this type of water heater in an RV..

I would use this link with the service manual and troubleshooting section...

https://www.rvupgradestore.com/v/vsp...e%20Manual.pdf

* you should be able to TS and find your issue with the above info

[Pthornburg10]

Originally Posted by Cheesehead4Life

In addition to the above, make sure the outdoor shower valves are off. If open that can cause the hot and cold water to mix in the lines.

You're an absolute genius!!! That was it!!! Thank you and everyone else for providing suggestions.

[xrated]

Originally Posted by Pthornburg10

You're an absolute genius!!! That was it!!! Thank you and everyone else for providing suggestions.

I guess I'm a few minute too late for that reply. Don't feel bad....every single brand of RV that has the outside faucet/shower outlet that has the two knobs on it will cause that, if they are left in the open position. Glad it was a simple fix for ya, now file it into memory!

[Pthornburg10]

Trust me. That's being logged into memory bank. I was up all damn night trying to figure it out. I couldn't sleep. My wife finally told me to shut it down.