Save Water! Kitchen Faucet with Foot Pedal

Clean water is more valuable than most of us realize. Clean water requires energy, so by conserving water, you're also conserving energy! You can help minimize its waste by installing a foot pedal to control your kitchen sink. We're going to install a couple of solenoid valves under your sink, and wire them up to a simple pedal. It's easier than you think, and you don't need any plumbing or electrical experience to do it. So, let's get started!

(If you like this Instructable, please vote for it! If you don't like it, please vote for it anyway leave feedback below so I can make it even better.)

Step 1 Parts: The Solenoids

The heart of this project is a solenoid valve. Very simply, these are small bits of pipe that have a valve that will open or close when you apply electricity to them. I picked these up on eBay for about $15/ea (here's a search link to help).

Solenoid valves have a few important attributes:

• the type of voltage required to activate them
• whether they're open or closed when they're unpowered, and
• the size or flow rate they will support.

For this project, we're going to want a pair of 12V DC, normally closed valves that will support about 3 GPM (gallons per minute). Typically, the larger diameter of the "pipe", the larger the flow rate. I went with 1/2" solenoid valves, and they're more than adequate for this project.

Comments

[Robnelson]

These solenoids are from a clothes washing machine, so if you are throwing out an old machine, you could take them out first.
You can buy some spade electrical connectors that crimp onto the wire and then plug onto the solenoid instead of having to solder them. They are much easier to remove if you ever need to replace anything.

[BGreenHVAC]

In my old workplace, there was a manufactured sink with a bar you step on to activate the water. When your hands were greasy from work you could wash your hands without making because you didn't have to touch the faucet handles.

I always wanted a similar device. I feel stupid for not building one before. I had this knowledge, but never thought about it. Thanks for the instructable. I'd make one eventually.

[grysqrl]

Have you encountered any issues with leaving the solenoids under pressure for extended periods of time? Might this have any effect on the life of the part or eventually cause leaks?

[BGreenHVAC]

That is the purpose of a solenoid. They are under pressure until activated.

[pjamestx]

It hasn't been a problem so far. I tend to do my kitchen cleaning in batches, right when I get home from work, and again just before bed, so when I'm doing that I'll leave the water on, and I tend to turn it off when I finish up. I have forgotten a couple of times, and turned it off in the morning, and I haven't noticed any problems. The valves I used are closed in their powered-off state, so I imagine they'll be fine, unless you have some crazy high water pressure or something.

[Rocky Top]

Thanks for your great Instructable!

Here's an idea that I tried and works like a champ.

I wired both the hot and cold solenoid together (in parallel) to a single doorbell button. I mounted the button behind the cabinet door under my sink such that it holds the cabinet door open just a small fraction of an inch. When I need water, I push the cabinet door forward with my knee which depresses the button and closes the circuit. The volume and temperature are controlled with the faucet handle, the flow is turned on and off with my knee. It's nice that no switching device is visible to the casual observer in the kitchen.

[LucifeL]

Dude your totally Awwwsome

[techno_sleuth]

There is a mechanical device which can be retro-fitted to any sink tap( as long as there is a control valve under the sink, with a flexi-hose leading to the sink tap).
Have one for several months now. Does not consume power and installation is a cinch with no plumbing experience needed.
Check out http://watermiser.hpage.com

[zchampine]

Cool, but how does this save more water than regular valves?

[pjamestx]

All by itself, it doesn't save any water. But I find that when I'm doing dishes or cleaning the kitchen, my hands are often occupied, so I won't bother turning off the faucet when I'm not going to be using the water for a few seconds. With this, I find that I'm much better about stepping on the pedal only when I need the water, so for me it's helped a lot :)

[larsrc]

You can get good foot pedals from old broken sewing machines. I happened to get one, and I'm of two minds whether to use the pedal for this or with the nice, heavy motor it came with.

[willywillya]

This is so cool. . .and. . .simple.  I am building a house and have checked out every sort of peddle valve device.  Was about to order the water pressure controlled remote device, but have held off , not only  due the the high price but was concerned about committing to custom replacement parts.

Couple of questions:  Think a brass bodied valve might be worth an extra fifteen bucks?  And. . . I  will install a gfci outlet and a small transformer (doorbell? suggestions?) .  Would it be worth the extra complication of switching this outlet to save energy?

Also I am considering tossing in a couple more valves--they are so cheap-- and hooking them up to a pull out hose with thumb nozel.  I could charge it with a wall switch and set the temperature (more or less permantently) with a couple of ball valves under the sink.  The idea is to avoid having the hose under full time pressure.  Anybody have any thoughts?

Thanks a ton,

Willy

[pjamestx]

Glad you like it!  Once I finally got started in this project, it came together surprisingly fast.  As far as brass valves go, I don't know how long the plastic ones I'm using are going to last, so it's hard to say.

You should be able to find a DC "wall wart" that would be compatible, if you don't have one lying around check Radio Shack or a similar place.  I'm guessing that having the adapter on a wall switch might end up making it a little harder to use (one more thing to remember).  On the other hand, you could always just leave the switch on, if it turned out to be a pain.

I've been looking for some different valves for the next iteration of this project, but haven't been able to find exactly what I'm looking for yet.  If I was going to do this all over again, I would probably find "normally open" (NO) valves, as opposed to the "normally closed" (NC) ones I use here.  When other people use the sink, they will forget about the pedal or don't like using it.  If I'd used  NO valves, the faucet would operate normally until the valves were energized, and the logic of the pedal would be reversed (pressing down on the pedal would break the circuit, causing the valves to re-open).  If you're only designing for yourself, then you can have it behave however you like, but if there are others that are going to be using it, you might want to be able to switch it to normal faucet operation (you can accomplish that with my design, but it involves keeping the valves always energized, which seems like a big waste of electricity).

[Indy]

When shaving at the bathroom sink with a razor. I'd love to have foot pedal that activated water at a specific temperature (hot but not scalding) to wash off the blade between strokes.  I often find my other hand is covered in shaving cream or otherwise occupied stretching my face into comical shapes and that I'm constantly trying to find the right temperature between water bursts.  This would probably save water and speed up the shaving process.  I guess in your setup, you can set a water temperature mix and leave the faucet in that position?  So really, I'm just advocating for a bathroom sink instillation.

Also, with respect to neiljackson1984's idea about fixed amount of water, I wonder if the automated soda fountain mechanisms used behind the counter at fast food restaurants would be useful.  Many of the worker-used fountains have buttons for fixed volumes (eg. fill this size cup).  It may simply be those dispensers have good consistent flow rates and simply need programmed timings in an Arduino.

[dawgz031]

really nice instructable.....
and great work with the solenoid....


im just thinking if i replace the solenoid with something...like a stopper from a **********...it might just work......but think i will leak out......as soon as i solved it i will post my solution.......

but for now...try to think what is ***************.......its from some where in your basement or in my house its in the kitchen....try to find out....

[frugalguy]

You could also switch to 3 pedals: cold, hot, latch. Tapping the latch pedal will open both valves fully, giving you the same behavior as your push-button (manual control). Tapping it again quickly would give you just cold, tapping again quickly gives you just hot. Tapping again quickly shuts it all off.  After 1 or 2 seconds, tapping any pedal also shuts it all off.

I really like the idea of fixed volumes of water being delivered. A tap of a hot or cold could deliver 1 cup. You could just time it if you can't get the flow-meter. 2 taps give 2 cups, 3 taps gives 4 cups.

[Subconscionaut]

Anyone figure out how to do it without using ANY electricity yet?(for less than a thousand bucks? some such double-bass drum pedals with pressure sensitive valve whatnot?
wish i knew more about plumbing...
anyone know a good book or site?

[pjamestx]

Yeah, check out this shower water pedal instructable.  It covers a lot more than just the water control, but it might have some ideas for you.

[Subconscionaut]

BTW pjamestx AWESOME ible you rock!

[neiljackson1984]

You ask, "what other possibilities are there with a setup like this?". Well, I'll tell you: temperature control and rate-of-flow control. Get two servo-controlled valves that can provide an electronically controllable range of resistance to the flow of water through them. Figure out how to mount a temperature sensor in the output water stream to measure the temperature. Install user-accessible dials for temperature and rate-of-flow. Hook the servo-valves, temperature sensor, and dials to the Arduino, and and then program the Arduino to adjust the servo-valves in order to obtain the dial-selected temperature and flow rate. I suppose you could even add a flow-meter to the output stream, so that the Arduino could precisely control the rate-of-flow. With such a setup, and with a sufficiently accurate flow-meter, and sufficiently responsive servo valves, you could have the Arduino dispense measured alequats of water of any desired volume. This would be great for recipes that call for a given volume of water.

[neiljackson1984]

Great minds think alike: I have also had this idea in my head for a while. It's great to see that you've gone to the work of building it.

[nert]

how about adding threaded 'T's before and after each (normally closed) solenoid and using an in-line ball valve for the hot and cold sides. simply reach under the sink and open each valve to set up for using the mixer handle. close the valves to return to foot switched solenoids. with some creative routing of tubing you could mount the valves near the front inside of the sink cabinet to avoid having to get on hands and knees

[l2f]

Hello, Use some pedals like the one you find in hospital (ER) non electricity, don't have to recharge the batteries etc.

[Boss_Sauce]

Those are very expensive, though, and aren't something that can be retrofitted easily.

[tristantech]

This is a cool project! However what about considering these things?

• replace the alkaline batteries with some more powerful battery. a nine volt battery in series with two double-a's won't last long. The 9 volt battery has much less current output that the AA's, which means your voltage will quickly drop.
• Get rechargeable batteries and put a waterwheel and generator into your water line and use the flowing water current to charge the batteries! :-) (no, that'd be REAL cool)
  

[pjamestx]

Good advice! I need to take some new pictures, I have in fact updated to a pair of 4xAA holders (I only used the 9V because it's what I had on hand), and I will probably look at switching over to a DC adapter pretty soon because the setup has been pretty solid (no leaks, which was my biggest concern). I do use rechargeable batteries and a solar charger, I think the water wheel is a little beyond what I can do :D But I'd totally love to see it if you made it work!

[brenthirak]

GREAT! and good explaination too! thanks loads!!

[peer2peer]

I think it's great that you're considering ways to conserve water availability through design! You should check out Carolyn Schaeberle, an Industrial Design graduate whose work, “Beyond the Tap,” has developed innovative ways for improving water transport and maintenance in developing countries.

Carolyn, and other sneak peeks from the Pratt Show on May 12-15th, can be found on our blog, Pratt Success! http://prattsuccess.blogspot.com

[pfred2]

Ah aren't we supposed to be using all the water melting off the polar ice caps? But seriously now there are more important things to worry about than all this eco nonsense. The planet was here long before the human race was, and it'll be here long after we're gone too! In the meantime, while I am here, I want to live as large as Al Gore does. Honestly when I run my water it comes out of my well in the front yard to my septic field in my backyard so all this solenoid would do for me is use more electricity than I already am pumping the water around.

[DIY-Guy]

Fantastic instructable on solenoid controlled sink faucet. I'm enjoying the constructive comments regarding improvements and upgrades. In my home we would like to see something with one solenoid valve controlling a mix of hot and cold water (after using the hand knobs to mix the ratio to our individual preferences.) In the Spokane (state of Washington, united states of America) area, the giant glacier which covered the area from Montanna, through Idaho and into Washington, finally melted away in the early 1800's. Both the natives and the settlers have oral and written records of the change. It was part of the current (naturally occuring) weather events. Political pundits are claiming around the world that the industrial activities of mankind are responsible for melting glaciers. Industrialization occured about 100 years AFTER our local giant glacier melted. Conclusions: Either (1.) we've managed to send our pollution through a time machine into the past and started "global warming" 100 years before the age of oil and industry; (2.) or, the situation has very little if anything to do with our activities; (3.) or, the media hysterics about the subject is another case of brainwashing the public for those who will gain profit or power at the expense of the public.

[EmmettO]

As far as the electricity that the switch uses, I think you've got it backwards. Especially for you, having well water. The less time your sink is running, the less time your well pump is running. The well pump takes far more electricity than the solenoid does. "Green" concerns or not, it would save you money by reducing your electric bill. In addition, it would be less mechanical wear and tear on your pump and septic system. If anything you would have more to gain by this than anyone with city water.

[pjamestx]

Well, he seems quite happy with the way things are. Like my dad always used to say, "you can lead a horse to water, but you can't get him to install a pedal activated dual-solenoid system to conserve it". I always assumed it was the medication talking, but it does seem rather appropriate in this situation...

[Subconscionaut]

rofl

[Lithium Rain]

xD

[mefromliny]

I guess that however you heat your water is free? This is a great way to say hot water costs... Ken

[pjamestx]

Oh man, I hear you. I'm totally with you on that. Screw the planet man, I gotta tell you, when nobody's around? I like to go outside and punch the Earth. I'll just go out in my back yard and BAM! Take that!

Sorry you didn't find this useful :) I didn't find any Instructables about it, but there are some good articles around about solar powered well pumps, maybe you'd get some use out of something like that?

[pfred2]

Why would I want expensive, inefficient, panels of arsenic poison around?

http://en.wikipedia.org/wiki/Solar_cell

Even the article you link to admits the only advantageous use of solar electric is when, (and I quote) "remote applications where a solar-powered water pump is more cost effective than installing a conventional grid-connected AC pump."

We're talking miles of cable here to hit the break even point.

Solar electric makes absolutely no sense at all anywhere where electrical grid connection is feasible. Well not unless you are worried about the imminent collapse of society and really need that morning cup of Joe to get going.

Use tools, don't be one.

[pjamestx]

Aww, sweetie, I love you too! I keep telling you, we're both on the same side :) I hate the planet just as much as you do, which is why I keep coming up with worse and worse ways to treat it! Tell ya what, let's team up, tonight around 8pm CST I'll go out in my yard and hold the planet down, and you go out in your yard and give it what for! Get medieval on it! And I'll totally say that it "fell down some stairs". You'll feel better, I promise! Kisses!

[Subconscionaut]

super lol- beat it with oranges! plant an orchard!

[pfred2]

No going medieval for me, I usually use power tools to teach the Earth who is master. Though sometimes I use an axe, or maybe a brush hook, or even the good old machete to beat back the wilderness. I even have two string trimmers, one wire, and one with a brush cutter head on it. Some days I'll burn through 2 or three tanks of gas if I really do a thorough job. Around here a day without chainsawing down a tree literally can be a day without sunshine. I am gearing up right now for a round of chemical warfare against the weeds and the bugs. I take no prisoners!