# Water spray system



## VashTLD (Jul 1, 2013)

Hello everyone! I had a quick question about a project which has been frustrating me for the last few days. We have a water fountain prop in one of our haunts which, when triggered by an actor, will mist water out. I have a simple push button wired up to a 2-way solenoid. I wish I knew the proper term for the piece I am using to connect to the water tank but I do not. It is a small metal piece with two 1/4" connections and one ribbed connection on the bottom. 

The problem I am having right now is with stopping the water after the button is released. When the system is triggered it works - air goes through the solenoid, hits through the connection I am using on the water tank and then brings water and air out the other end. The only problem I am having is that it is not stopping! It seems the solenoid is getting stuck and it will continuously spray water which makes a dangerous mess for patrons. If I tape the coil on the solenoid the water will stop spraying. I have tried multiple 2-way solenoids which all yielded the same result. Interestingly, if I hook up the system backwards (wherein no water comes out) the solenoid does not stick.

Does anyone have a solution? This has been driving me crazy for days. Thanks in advance!


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## craigsrobotics (Oct 12, 2009)

Are you siphoning water through the valve body, or are you using a "T" where the air from the solenoid blows through the horizontal piece (venturi effect), and the vertical piece of the fitting is inserted into the water container? If the latter, then you really need a check valve so the water doesn't siphon back into the valve when deactivated, especially if it's not a valve designed to handle water..


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## Hippofeet (Nov 26, 2012)

Ive never used a 2 way, always a 3 way. I hate to ask, but the are you running the air through the solenoid the right way? I have had some stick when I run high pressure and Ive run the air INTO the OUT. Since it has happened with multiple solenoids, I would rule out a bad solenoid.

I would also be curious if you are running a venturi, or pressurized system. 

I don't use check valves in venturi set-ups, I find they cut down on some airflow, and I lose suction distance, but I totally agree with those who do, and understand why they do so. I compromise, and go with recommending installing the solenoid higher than the sprayer outlet if possible, or at least blowing out the lines overnight, or adding a loop to catch back flow, if it can't be set up that way. I see the check valve come up a lot, maybe I need to go with a 1/2 inch check valve, and see if I like it better than using one the same size as my airline. Could be that simple.

I could wish for a picture of your set-up.


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## craigsrobotics (Oct 12, 2009)

Yeah, visually, I am picturing his setup with a "T". I personally use a setup similar to a "wishbone" venturi effect, feeding a 1/8" water line diagonally into a 3/8" airline. The output fitting from my solenoid valve has a check valve on it, so nothing flows back into the output port of the valve. The tip I use for the sprayer outlet is also "checked" or one-way with a small check valve in it, so water is always present in the water line (i.e. the system retains a slight amount of pressure to hold water and air in the lines)


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## VashTLD (Jul 1, 2013)

Thanks for the response guys.

@craigsrobotics

Yes, I am using the venturi effect. I do not currently have a check valve in place, I will have to salvage one and try hooking it up to the system to see if this fixes the issue.

@Hippofeet

I do not remember if I have tried a 3-way solenoid yet. This project has been giving me problems for a little while now so I have typically put it aside while finishing other things, unfortunately most all other things are now finished so I have to finish it. The air is hooked up the solenoid the correct way, however I did try reversing the lines to see if that was the issue.

I have drawn a diagram of my setup. I will not have access to the prop for a few days so this is the best I can do for now, sorry. Thanks for your help guys.









Lines from the regulator are 1/4" NPT. I am putting between 60-80 PSI through this prop. Currently, the solenoid is about level with the water tank but far lower than where the water sprays out, so as Craig said, it is possible small traces of water may be running back in to the solenoid. I will try the check valve on Sunday.


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## Haunted Spider (Sep 6, 2010)

So you are wanting to shoot a stream of water at the patrons like the fountain is out of control, or you are shooting a mist they can't see so well but they get wet by?

If you are shooting a mist, go to a junk yard and get a windshield wiper sprayer. It has the solenoid, the power system, hoses and tank all together. Just power it with 12v dc and it sprays. Cut off the power and it stops. 

If you are wanting a stream of water then nix the above suggestion.


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## VashTLD (Jul 1, 2013)

Just a mist - we don't want to soak anyone or create a slipping hazard. I had thought about a windshield wiper motor considering we have around twenty junk cars which are used as props - however, don't these put out too much water? I nixed the idea after reading somewhere that they spray water rather than mist it out.


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## Hippofeet (Nov 26, 2012)

Ok, given that drawing, even though I haven't experienced a stuck solenoid (and I've set up a few just like that) I would have to go with craigsrobotics. I just can't think of anything else it could be. There must be enough length of line, and height, to get a good flow of water back down the line into the solenoid. I would still think that the solenoid would just blow this out when you hit the button. I mean, whats causing it to stick? Deposits? That would take time. Water going up into the release passages when the piston rises? You would see that as leakage on the body of the solenoid.

Hmmm. You know... The coil is pulling that piston up against spring pressure. It doesn't act to force the piston back down, and shut off the valve. The spring pressure, and some air pressure does that. It just may be that filling the valve relief passages with water would be enough to affect the valve. Sort of air lock the piston.

I only use 3/8 3 ways (for the simple reason that we have never ordered, or received an order, for a 2 way 3/8 solenoid), so any backflow into the valve, and the air passages, would have a way to vent, it would never air lock the piston the same way a two way valve might. I may have to soak a few solenoids over night, see if I can duplicate your problem with a 2 way or a 3 way.


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## VashTLD (Jul 1, 2013)

Thanks for the reply Hippofeet. Most of our stock is old, there has never been much of a dedicated position for animatronics and technical. This is my second year in this position so I plan on taking inventory, recycling a lot of old stock and ordering new. It's quite a pain to go through random boxes and find solenoids, controllers, triggers (PIR / Beam) and other various parts which either work, don't work or are some combination of the two. The issue comes up in projects like this, where I can't quite decide exactly what my issue is (whether these are old, busted solenoids or incorrect usage on my part). 

I'm going to try a few things when I go in on Sunday. I may try what Haunted Spider recommended first, by pulling a windshield wiper sprayer from one of our junk cars and seeing how that works. If that puts out too much water I will try a 3-way solenoid Valve with exhaust ports then try installing a check valve as recommended by Craig.


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## Hippofeet (Nov 26, 2012)

VashTLD, 

The only other Vash I know of is the anime. Which also has the T, but not the LD.

I take it you are working for a haunt? Which has an actual position for a tech? lol. I hope that doesn't catch on, I will lose money.

Good luck with the sprayer, and if you could, post on how it turns out, even if the windshield washer turns out to be the bee's knees. I am still going to do the experiment, it may change the design of our sprayer mech's. I can't control how customers set up some things, and if a check valve makes it more foolproof and avoids the possibility of a failure, it's worth the time for me to figure out the how's and why's. 

So, thank you for the question.


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## corey872 (Jan 10, 2010)

Don't suppose you are running DC power to an AC coil, or overvoltage to a DC coil? Either case may saturate the magnet and cause it to stick. What happens if you reverse the power wires?


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## VashTLD (Jul 1, 2013)

Thanks Hippo. VashTLD is actually quite an old name, I signed up with this name and intended to lurk. Never actually thought I would post. Vash is from the anime, as you said, but "TLD" use to mean "The Level Designer," as I do game design as well. 

The tech position kind of came about naturally, really. I worked as a laborer my first few years, putting up the houses and running electric. Then I started doing music, last year I gave a bit of consultation for the new event website and now my primary focus are the air and animatronic systems while still doing sound effects and music. I set up all of our props, troubleshoot systems and research new tech for future years shows while maintaining the haunts during the show. 

I will definitely post the outcome within a week or so. I will take a few pictures, draw a diagram and detail which parts I used in the hopes that it will help the next person who runs in to this issue.


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## VashTLD (Jul 1, 2013)

corey872 said:


> Don't suppose you are running DC power to an AC coil, or overvoltage to a DC coil? Either case may saturate the magnet and cause it to stick. What happens if you reverse the power wires?


I have tried different solenoids to see if this was a power issue, all produced the same results. First was 120VAC solenoid then I moved on to a 12V which is powered by a wall wart.


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## oldpro (Oct 11, 2011)

It sounds like the spool valve is sticking. 
Take it apart and clean it out and make sure no debre is keeping
It hung open. Could just be corrosion in the valve , 
Especially if its used.


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## bfjou812 (Aug 15, 2008)

If the solenoid is rated for air and water the easiest thing to do would be put the solenoid on the other side of the "Tee" fitting. When I have wanted a mist I've always used universal windsheild washer pumps. They are usually fairly cheap and powerful so I use a tip from a pressure washer to get the mist.


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## Hippofeet (Nov 26, 2012)

Okay, I soaked two solenoids overnight, just pulled them out of the water, threw on a dc coil, and tested at 125 PSI. No affect on performance whatsoever. 

So... I dunno.


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