One way valve on hot water in shower

Buy a Sharkbite check valve. Link

Cut the red PEX tube coming out of the water heater and add push the valve onto the line being careful to observe the water flow arrow.


Are you having a problem with the cold water blast in the shower or does the one way valve just seem like a good idea.

Many RV water heaters already have a check valve at the exit line, it's possible yours already has this.

Does your RV shower head should continue to dribble water out of it even when you flip the switch off. This is to prevent the cold water blast as the pressure can't build up enough to backflow the line.

If your shower head shuts completely off, you can avoid the cold blast by only shutting it mostly off. Leave a little dribble out of the head and the cold blast won't occur.

Need access to HOT water line to shower faucet
Then install a check valve in Hot line

**Doesn't have to be right at the shower faucet ...just needs to be on Hot line going to shower faucet

What I've done to fix that problem is to put a garden hose/GH valve at the shower head. I get from Tractor Supply water pipe to GH adaptors.

Dusty

I used one of these between the hot water pipe and the hot faucet, and then I added one of these at the base of the shower head hose. No more icy or scalding water when taking a Navy shower in the TT. Pretty easy install.

arcsum68 wrote:
Per the video when you use the switch on the showerhead to shut off flow, the cold water will back fill into the hot water side since the pressure is greater and thats why when you turn it back on it will be cold for a few seconds.

Since both the hot and cold water are pressurized by the self same PUMP that.. it male bovine produced organic fertilizer (AKA BS)

What happens is when the water stops the hot cools a bit and "Contracts" sucking cold in. The solution is to use a better valve that does not 100% turn off flow. the Oxygenics "Smart Pulse" valve is like this. it allows a dribble of watter to flow. So does the generic valve I got at Mennards years back (Alas no link it's been 15 years)

Either of these solves the issue for about 10 bucks.

wa8yxm wrote:

arcsum68 wrote:
Per the video when you use the switch on the showerhead to shut off flow, the cold water will back fill into the hot water side since the pressure is greater and thats why when you turn it back on it will be cold for a few seconds.

Since both the hot and cold water are pressurized by the self same PUMP that.. it male bovine produced organic fertilizer (AKA BS)

What happens is when the water stops the hot cools a bit and "Contracts" sucking cold in. The solution is to use a better valve that does not 100% turn off flow. the Oxygenics "Smart Pulse" valve is like this. it allows a dribble of watter to flow. So does the generic valve I got at Mennards years back (Alas no link it's been 15 years)

Either of these solves the issue for about 10 bucks.

another possible cause of the cold water problem is WH bypass systems with ONE lever, rather than the TWO lever systems. The one lever systems use a one way check valve that often has highly non linear characteristics. The result is very noticeable water temp changes with flow, very noticeable when water is down to a trickle then back up again. Solution, pull the check valve that is installed and install a WH bypass with two levers. That solved our issue along with two other camper friends complaining about the same problem.

opnspaces wrote:


Are you having a problem with the cold water blast in the shower or does the one way valve just seem like a good idea.

Many RV water heaters already have a check valve at the exit line, it's possible yours already has this.

Does your RV shower head should continue to dribble water out of it even when you flip the switch off..

Thanks all for answering.

I get a cold blast every time, so it seemed like a good idea. If mine had such a valve, would this not be an issue or is what I have about as good as it gets? Pretty minor complaint, just trying to make things nicer.

I have an Oxygenics shower head and it does indeed dribble when turned "off".

I tried most of the “All you have to do is just.........” suggestions given here, with very little improvement. I say “most” because when you dry camp as often as we do, and only have a 30 gallon fresh water tank, dribbling the water works against our need to stretch every resource needed to extend our stay.

What finally fixed it for me was a Thermostatic Shower Mixer Valve.

:):)

NRALIFR wrote:
I tried most of the “All you have to do is just.........” suggestions given here, with very little improvement. I say “most” because when you dry camp as often as we do, and only have a 30 gallon fresh water tank, dribbling the water works against our need to stretch every resource needed to extend our stay.

What finally fixed it for me was a Thermostatic Shower Mixer Valve.

:):)

I mostly dry camp as well, and my trailer only has 40 gallons fresh water. It's really the one negative thing I have to say about the trailer so far, very small amounts of fresh and gray water storage. Even 50 gallons each would have been very much appreciated.

I love this idea, but I think I will be pretty limited since I have no access from the outside. The only place I can do anything from, is the inside of the shower at the valves or maybe inline. There is an access panel for the water heater/heater, but I havent opened it up yet.

In the video I watched the guy had a room behind the shower and cut into the wall so the check valve was right at the controls.

Hmmm, looks like this guy did it without having access to the rear. This sounds SUPER appealing. I am going to investigate, but I really like this idea.

https://wackypup.blogspot.com/2019/09/best-low-cost-luxury-mod-upscale-rv.html