When we leave our RV at a FHU campground to go sightseeing, shopping, etc., I try to remember to turn off the city water supply at the pedestal. To make this process a little simpler, I am considering plumbing a normally closed 12v solenoid water valve in the wet bay to turn on and off the city water supply controlled by an illuminated toggle switch located by the entrance door. I found one mention of installing a 12v water valve on another RV forum but can't find if anyone has done this. Any thoughts on the up-side or down-side of this idea.

Hows about this idea? Use a garden sprinkler timer. They're already setup to attach with garden hose type fittings and already contain the right kind of valve. Time for a shower or washing dishes or laundry set the timer for a few hours and done. No need to remember to turn it off, or work with any wiring.Other than that, lawn sprinkler diaphragm valves are rated for 24 volts AC but work just fine with 12 volts DC. Get a 3/4" valve and some NPT to garden hose fittings and then wire the switch up wherever. Although not specifically advertised as drinking water safe, I don't see anything inside a sprinkler valve that would be toxic. The body is PVC and the diaphragm is neoprene.

Only downside might be loss of 12 or 120 volts? But you could make it fail-safe by having it open when power is present but would have a 12 volt draw to consider if using 12 volts. I think you'd want it closed when there is no 120 volts present because CG power can potentially go off when you're not there (happened to us a couple of times so far). I don't think the current draw on these solenoids is much.If on 120 volts, you could also use a latching relay and "momentary on" switch/pushbutton so water is off until you intentionally activate the relay. That way, any time power is cut off (intentionally or not) the valve would close. One thing I do when hooking up the water in a CG is run inside to make sure no water is flowing that shouldn't be. Had an overflowing toilet incident once because the CG pressure was quite low (luckily we were there at the time).I installed a quarter-turn ball valve under the kitchen sink and while it does work and will never fail, it sure would be nice to have a switch that would be easy to activate.downtheroad wrote:This is a simple solution also....Can't see the pic. Time to quit using Photobucket. :)

Let's see the valve will be in the RVLeaving the hose pressurized and in the sunIf i did this i would use a sprinkler valve they are designed for City water pressure, much more durable than a smaller 12v valveUse A 110v to 28v transformer to power the valve

MrWizard wrote:Let's see the valve will be in the RVLeaving the hose pressurized and in the sunIf i did this i would use a sprinkler valve they are designed for City water pressure, much more durable than a smaller 12v valveUse A 110v to 28v transformer to power the valveThe 12V solenoids I randomly checked were good to 300 PSI with a working pressure of 30-120 PSI, if you've got over 120 PSI coming into your rig you've probably got bigger problems and should have had a pressure regulator upstream of the valve anyways. It's not like those valves aren't used for thing on normal water service, that's probably 90% of the use case. In fact when I checked my favorite electronics site they said the valves they had all required regular water pressure and if you were using a solar powered pump that you'd have to get a different kind of solenoid from a different supplier.

Those diaphragm valves often times are used with big irrigation pumps, way more pressure than you'll typically see in a residential or even campground setting. Good point on the sun affecting the feeder hose.... why not just screw the electric valve straight onto the water hydrant? Probably good to protect the valve body from the sun also, since they're designed to live in a basement or be buried underground out of the sun.

Control city water supply with 12v water valve | Good Sam Community

31 Replies

TNGW1500SE
Explorer
Oct 30, 2017
the2sharps wrote:
A final report on this project. The solenoid water value would get hotter than I was comfortable with when it was activated in the on position. I changed to a normally closed motorized ball value and the project works great.

Interesting. I wonder if it was designed so the moving water cooled it.
the2sharps
Explorer
Oct 29, 2017
A final report on this project. The solenoid water value would get hotter than I was comfortable with when it was activated in the on position. I changed to a normally closed motorized ball value and the project works great.
myredracer
Explorer II
Aug 06, 2017
I wonder what is available for a low flow monitor that you could connect to the solenoid valve to prevent damage from a slow leak?

In view of our toilet valve experience that let water flow into the bowl when the CG pressure got down to around 10 psi, maybe a low pressure shutoff also might be a good idea.
thedoghouse
Explorer
Aug 06, 2017
the2sharps wrote:
thedoghouse, here are the two main parts I used. I bought them through ebay.

- 3/4 inch 12V DC VDC Slim Brass Electric Solenoid Valve NPS Gas Water Air N/C

- Heavy Duty Universal 12V Remote Control Kit 15amp

I mounted the remote control switch in the wet bay and the fob switches it anywhere in the motorhome.

Also, I decided to put a manual switch in the wet bay to turn the power off of the remote control switch when I'm not connected to city water.

Thanks ??
the2sharps
Explorer
Aug 06, 2017
thedoghouse, here are the two main parts I used. I bought them through ebay.

- 3/4 inch 12V DC VDC Slim Brass Electric Solenoid Valve NPS Gas Water Air N/C

- Heavy Duty Universal 12V Remote Control Kit 15amp

I mounted the remote control switch in the wet bay and the fob switches it anywhere in the motorhome.

Also, I decided to put a manual switch in the wet bay to turn the power off of the remote control switch when I'm not connected to city water.
thedoghouse
Explorer
Aug 06, 2017
Nice MOD. Some wil like and some won't. I like it and plan to do. If we never tried and changed things where would we be. Wow. THANKS
the2sharps
Explorer
Jul 31, 2017
No, but that's an idea.
Bird_Freak
Explorer II
Jul 31, 2017
So whats next? Are you going to get so lazy you want to hook to Alexa so you can tell it to turn the water on and off for you?
Think I will just turn the knob.
the2sharps
Explorer
Jul 31, 2017
Next step, the install of the water value control plumbing in the wet bay is almost complete. Still need a couple of more bracket screws. Next is running a 12v line through the RF switch to the valve. I have several options on how to run the wiring, not sure which one I'll do yet.
afidel
Explorer II
Jul 31, 2017
Bravo, love the work, it's nice when you can scratch that itch that no off the shelf solution will fill.