DREAMING. Controlled Shower Water Temp

Mr Wiz, brass adapters are included with the fixture. They bring the spacing from 6 " to a little over 4", not quite 4". Then you pull original PEX pipes in the wall slightly wider to match the adapters. Here is the video that explains the install:

Thermostatic Shower Valve Install.

I don't know why you need access from the other side of the wall, maybe your plumbing is different.

He already had the "box" on the wall, many trailers don't, I know people had to cut the PEX pipes shorter and use Shrakbite fittings.

If I set water heater lower, I will need to mix more hot water in, and will run out of hot water sooner. Unless I misunderstood Time2roll.

unless i make a bigger hole in the wall in the bedroom for the access hatch
i can't use the 6" center
the existing hatch plate, does not allow enough access for 6" centers
a plate in the shower will not change that

i don't plan on enlarging the hole in the bedroom wall

if you have a link to those 'little elbows'
please post it, i haven't found anything the right size
to work with out butchering the wall and shower stall

Easier to get the mix right if you turn your water heater down closer to the desired temperature.
Otherwise get something like pictured above.
Not rocket science.

wa8yxm wrote:
Re the 4" centers. You may notice the one in the photo was mounted on kind of a box..

HDPE cutting board. Behind the board (I think) are little elbows to bring it from 6" to RV 4", this is in another guy's trailer. This one is without a bathtub faucet, but they come with faucets too, google for Cherry Juilt Thermostatic Bathroom Shower Mixer Valve.

Quality... about as that of a cheap Walmart or Home Depot diverter, 15% DOD, the rest work, until they don't. You still need to twist the knob while holding the red button to change/make it hotter. Not really tap-tap, "Alexa, 108F please and one martini stirred not shaken".

Re the 4" centers. You may notice the one in the photo was mounted on kind of a box.. Yup re-drill put a mounting "Box" over the existing holes and seal the box to the shower stall. Job done Looks professional. And works.

I was going to suggest one of those but he beat me to it

Electric point of use heater under thyristor control, one or more valves and a small pump allowing the water to loop through a heater rather than stop, and a PID controller with a thermostat running the show.

Boot up would see the PID re-circulating water through the heater until program temp is reached. PID would cycle heater on and off via the thyristor to maintain program temp.

When user opens the valve on the shower head, only a brief second of off-temp water would be delivered, from hose. Closing the shower head valve, water would return back to the re-circulation loop.

Might need past employment from NASA to program and operate it, but sounds like a fun project.

i looked at them online
i can't find one with 4" centers to install in my RV shower

CJW8 wrote:
thermostatically controlled mixing valve

You mean like this?

CJW8 wrote:
It could be done with a thermostatically controlled mixing valve as is done in S & B house.

There are dozens and dozens of thermostatic mixing valves and faucets with integrated thermostatic mixing valves available on Amazon and eBay. A lot of them are very reasonably priced.

:):)

Dreaming is not a problem for me

But I encounter a vast multitude of "Is's" and "Ought To Be's" every day. The problem is the emitters of confusion are incapable of learning which is which...