DIY Electric shut-off valve

[toofazt]

Your welcom Glad I could help.

[toofazt]

Originally Posted by 66 north

I'm going to do this if I can find everything, were the PVC fittings easy to come by?

Yeah, they're easy to find. Just go to Homedepot or Lowe's and look in the plumbing section. I just found the 1'' sprinkler valve, opened it up and went to the plumbing section to find the pieces I needed.

[scolley]

Hey Steve, do you know what the internal diameter of that lawn solenoid is? And if it has to remain pressurized to work? And if so, how much pressure?

I've already built a system needing these things, and I'm certain I over built (translated - stupidly spent too much).

Thanks. BTW - great name IMO.

[toofazt]

I don't know what the inside diameter of the solenoid it. Whatever your going to have flowing through it does have to be under pressure a little. I don't know specifically but it's not too hard to blow through with your mouth when it's engaged.

[scolley]

Originally Posted by toofazt

Whatever your going to have flowing through it does have to be under pressure a little.

Yeah, every liquid has to be under a little pressure to flow through a tube (generally speaking). But some solenoids, particularly the less expensive ones, use the fluid pressure to switch them somehow. So if you have a fluid that is not adequately pressurized, they won't close all the way.

You are using this for an RO system. That's got a good bit of pressure. I ask because some other application, like draining a tank, may not have as much pressure, and this lawn solenoid may not be suitable. So it would be nice to know if you have that info.

Thanks.

[toofazt]

This solenoid does not use fluid pressure to switch it. It uses the 24V transformer. When there is power to it, the valve opens. When the power is shut off, it closes. I do not think this would work for draining a tank unless you had some sort of pump hooked up to it, which would be pointless because you could just use the pump without the solenoid. Does that answer your question?

[jay1st]

But some solenoids, particularly the less expensive ones, use the fluid pressure to switch them somehow. So if you have a fluid that is not adequately pressurized, they won't close all the way.

You're spot on !
Most of the gardening electric valves uses this system.
A solenoid lets a small amout of water (master command) to push a spring loaded piston lifting a rubber membrane (slave) allowing a big flow of water.
Membranes have a tendancy to become porous over time, and the low ph out of the RO/DI will not help.
But it will take a while before it happens.

[scolley]

Thanks Steve. jay1st confirmed what I wanted to know. I all likelihood this solenoid will only work for moderately pressurized applications.

Which is fine for what you've got it doing. Great work!

[vidiots]

Originally Posted by toofazt

I needed a automatic shut-off valve for my RO-DI system and it had to be before the water line got to the RO-DI unit. So I decided to see what I could come up with. I went to Wal-Mart and got a Automatic Float Switch ($11.28) in the boating section. Then I went to Lowe's and got a 1'' Sprinkler Valve ($10.92) and a 24V Transformer ($12.97) in the sprinkler section. I already had the pvc pipe fittings (~$6).

Wow, that is a whole lot cheaper than what I spent on the setup for my auto water changer, and for the most part it looks like you got all the same equipment. Nice job!

I really should learn to shop around more when I do these things.

[jay1st]

Why not a soelenoid valve from an old washing machine ?
I know a lot of people who used it for years.
And it's free !!

[toofazt]

Originally Posted by jay1st

Why not a soelenoid valve from an old washing machine ?
I know a lot of people who used it for years.
And it's free !!

How big is a washing machine solenoid?

[jay1st]

It's like this :

Found here.

[Naja002]

Why not a soelenoid valve from an old washing machine ?

That is really too sweet. Never crossed my mind. I may try it just to check it out.

[Ken73]

Hi Guys, just out of curiosity, is there an advantage of this setup over using a regular Kent Marine float valve? I've got my trash-can RO setup with a mechanical float valve on it, and it's been doing fine.

[Brilliant]

Why not just buy a .25" solenoid valve?
I have mine wired into a timer....one of many thats left sitting around.

I really love the post DC has over at FellowshipoftheFish. I am revamping my source water system now and its been very helpful although the manual water changes are giving me a workout I needed.

Heres a pic of the splitter I use and the solenoid valve.