Poor-mans Automatic Sprinkler.




How to build a poor-mans automatic sprinkler. Forget the cheap battery powered ones. The battery ones always fail when your not home, ending up with wasted water and mushy sod.

Here is how to put together a cheap, reliable, rugged, automatic above-ground sprinkler set up. If your thrifty, you can put it together for less than $30.00!

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Step 1: Bill of Materials

Parts Required
One (1) 3/4 Sprinkler Valve - $12.99
Two (2) Male Hose Barbs - $3.47
One (1) Sprinkler Transformer - $14.96
One (1) Wall Timer - $5.97
Six (6) Feet of old hose - Free!
15 foot Extension Cord - $9.99
One (1) Y Shut off (Optional) - $8.97
Teflon Tape - $0.99
Zip Lock Freezer Bag
Zip Ties
Heat shrink tubing or Electrical Tape.
Sprinkler of choice.

That comes to a total of $57.35. The other battery operated units I have bought cost about as much. They all let me down.

The transformer I had sitting around from a prior job. I have heard you can use just about any voltage (AC or DC) to trigger the valve. I chose to use this because I know it wont damage the valve. Keep in mind that if you run an incorrect voltage you increase the risk of damaging the solenoid or starting a fire. You're on your own if you try a different transformer.

The hose, grab it out of your scrap bin. Alternatively, scrounge one on trash day. You really only need a couple feet.

Hose ends. I buy brass fittings with hose clamps from Big Lots. They cost as low as a dollar if you do a little searching. The Y adapters can be had for a couple dollars from the same location.

There are several sizes of valves. For some reason, it seems that the 1" valves are cheaper. The 1" valve will not work with a regular hose without reducers. Search out the 3/4" valves. These can be had from $11 to $13 dollars.

As you can see, you can easily drop the cost of the unit down below $30.00! Rock on, lets proceed.

Step 2: Assemble

Step 1.
Attach Both male hose fittings to the length of hose.

Step 2.
Generously wrap the threads on one side of the hose with Teflon tape and thread it into the sprinkler valve. Use pliers to snug it down nice and tight.

Step 3.
Generously wrap the threads on the Y shut-off with Teflon tape. Thread the Y-Pipe onto the inlet side of the sprinkler valve.

Step 4.
Cut the two bottom corners off the ziplock bag. Plug the transformer into the timer. Plug the timer into the extension cord. Run the transformer leads out one side and the extension cord out the other. Wrap the plastic around tightly around the wires and zip tie the bag to the wires.

Step 5.
Connect the transformer to the valve. Its not polarized, so just connect the wires (solder if you prefer), and heat shrink the connections.

Step 6.
Connect the Y shut-off to your desired faucet and the hose end to your desired hose. Set your timer and plug in your plug. Seal up the zip lock bag.

Step 3: Testing and Enjoying

Turn on the water and check for leaks. Open the Y and verify the valve pressurizes. It should not allow water to pass. Fix any leaks now. Turn your bleed screw and see if your sprinkler kicks on.

Plug it in, set the timer. Switch the timer to on and the valve should open. Switch it back to timer and enjoy.

Set the timer to go on early in the morning (Mine comes on for half an hour at 5AM. This will give the water a chance to soak into the ground before the afternoon heat. The timer will help you save water by soaking when most effective. Switching to a 7 day timer would allow you to save even more water by alternating days.

Here in San Antonio, if our aquafer drops below a certian level, we enter stage 1 water restrictions. This means we can only use automatic sprinklers once a week. A 7 day timer would let me comply. Once my new grass takes root, I plan on dropping to twice a week watering schedule.

Upgrades, Mods, tweaks?
7 Day digital timer - Give you programmable 7 day watering schedule. This is my next upgrade.
Water proof box. - Probably a wise investment. I intend to scrounge one of these from the junk pile at work.
Daisy Chain Sprinklers - Get all those dry spots.
Multiple valves - Water front and back yards.

Well, enjoy your lush green lawn.


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    15 Discussions


    3 years ago

    Did somethong similar with a clearanced sprinkler timer ($20 - returned over a missing plastic cover for the terminals), some used valves and a distribution manifold from St Vincent dePaul ($10 +$5 for a rebuild kit to fix a bad diaphram and some o-rings) and some scrap phone wire to hook it up...


    10 years ago on Step 3

    cant you set up the timer inside the house or in car port for easy access? then it would be out of the weather.

    1 reply

    Reply 10 years ago on Step 3

    Definitely, On the second unit I built. I extended the low voltage wire and mounted the timer/transformer in an outdoor electrical outlet that is protected by my porch.


    10 years ago on Introduction

    Those old water valves off from a old automatic washing machine should work fine also.

    Mr. Rig It

    10 years ago on Introduction

    You said if your thrifty it could cost less than $30 but you said you spent $57.35. So I am going to guess you were not being thrifty or were you? Either way great idea and great ible. Good Job!

    4 replies
    danzajaxMr. Rig It

    Reply 10 years ago on Introduction

    The $57.35 is what I priced from home depot. I actually had most of the items on hand from previous projects. The only real strange object is probably the sprinkler valve. I figured most people would be able to scrounge a transformer, hose ends, timer, and ext cord. Thanks!


    Reply 10 years ago on Introduction

    How would I go about using the design of your system, but have the water pump or the timer be "triggered" to ONLY come on when AC power is on and off when AC power kicks back off. If this doesn't make sense, I will elaborate, but I want to do an experiment and hook up a hose to an automatic water pump and wired into my outside air conditioner blower unit, but only have the water pump "activate" when the air conditioner kicks on and close off water flow once the air conditioner shuts back off. Thanks. Andy B


    Reply 10 years ago on Introduction

    I think your trying to say that you want the valve to open when your AC kicks on? I would just open up your air conditioner and solder a extension cord to the compressor terminals. That is, the AC compressor is supplied 110VAC power through a relay that is controlled by the thermostat. If you wired your transformer/sprinkler valve in parallel with the compressor, it will only open when the compressor kicks on, and close when the unit is off or the compressor is turned off by the thermostat.


    10 years ago on Introduction

    Thanks for the info, but did I miss the specs on the transformer? I most likely have one lying around the house.

    1 reply

    Reply 10 years ago on Introduction

    The units I use are 24VAC 650ma transformers. I am pretty certain that the valves can run on a variety of voltages from 12 to 30 V both DC and AC. I think the 650ma is enough for several valves. You should be able to find something at a garage sale or your junk bin. The Solenoids are cheap and replaceable ($8 at HD) if you do smoke one.