A Portable Automatic Filler Valve that hooks to Garden Hose

I have made a couple of these, they are handy for keeping livestock or outdoor pet's water tanks full at all times (make sure they are shaded all day long or you are in for some serious algae growth), or making tasks like filling a pool or large water tank an unsupervised affair. You can use what ever plumbing between that you want but getting from the 3/4" garden hose to the 7/8" fitting for the toilet fill valve is something most of the hardware store employees in my area have been unable to help me with.

Shopping list, total cost for materials that could be used again $9, total cost for parts around $20. It could cost less if you can get all your fittings in plastic, but I was unable to.

• An universal toilet fill valve (should cost around $8-12)
• A short section of  3/4" PVC pipe (around 3 feet is plenty for a filler like the one I am making, under $3)
• 2x3/4" PVC slip elbows (around $0.30 each)
• a 3/4" PVC slip to 3/4" female thread elbow (around $0.50)
• a 3/4" PVC slip to 1/2" female thread elbow (around $0.50)
• a 1/2" male pipe thread to 3/8" compression adapter (the only one my hardware store had was in brass, it cost around $3)
• a 3/4" male pipe thread to 3/4" male garden hose (once again only available to me in brass around $4)
• a 3/8" PEX faucet supply line (around $2)
• a small container of PVC primer and cement (the small 4 oz cans were around $4 each, and I hardly used any of it)
• a roll of thread seal tape (around $1 for a roll and hardly used any of it as well)

Here is a picture couple pictures of the PEX adapter so you know what you are looking for.

 

Lets get everything we need lain out and prepared so assembly will go quickly. First we need to cut our PVC, I used a hacksaw, we need 2 pieces around 3" long and one around 14"-15" long. To make sealing go smoothly take all the burrs off the inside and outside of your cut PVC ends, this can be done quickly with a round file.

A word of warning about using the PVC primer and cement in combination, it sets very, very quickly. You have at most 10 seconds after slipping the pieces together to line it up where you want it. After that, for all purposes of re-positioning a joint, the pieces are bonded on a molecular level. 

Assembling the plumbing only takes a few minutes once you have everything together. The process for gluing PVC pipe to the slip fittings go like this.

1. Swab the inside of the slip fitting and the outside of the pipe with the primer
2. Let that dry, it should only take a couple seconds.
3. Swab the inside of the slip fitting with the cement.
4. Press the pipe into the slip fitting as far as it will go, usually about an inch, as quickly as possible and get it oriented like you want it. As mentioned before it sets very quickly, so pretty much once you stop twisting the connection it will never move again.
5. Rinse and repeat with the next fitting.

I highly recommend the use of thread seal tape on the fittings that thread into the PVC. You will want to wrap the tape around the fitting clockwise 2-3 revolutions, no more than that though as it will cause binding when trying to get the threads started.

I have lain everything out on the table disassembled as it will be glued or threaded together, so if you are looking for a road map this picture is it.

For those of you who like a walk through I will start on the Garden hose end and work my way to the fill valve.

1. Thread the pipe thread into the 3/4" slip to thread elbow. (Use caution not to over tighten and strip the plastic threads out of your adapter.)
2. Glue a 3" piece of PVC into the slip side of the elbow.
3. Glue a 3/4" slip elbow to the assembly, make sure it is oriented so the next pipe you glue will be parallel to the assembly so far forming a U shape.
4. Glue the 14"-15" piece of PVC to the assembly.
5. Glue a 3/4" slip elbow to the assembly so that it runs perpendicular to the bulk of the assembly
6. glue a 3" piece of PVC to the assembly
7. Glue the 3/4" to 1/2" slip to thread adapter to the assembly so that it runs parallel with the bulk of the assembly.
8. Thread the 1/2" male pipe thread to 3/8" compression adapter into the assembly. (Use caution not to over tighten and strip out the plastic threads of your elbow.)
9. Remove the brass ferrule from the compression nut as you will be using the plastic ferrule that came with the PEX faucet adapter.
10. Cut the 3/8" PEX faucet adapter down to about 2-3 inches.
11. Put the 7/8" nut that came with the toilet fill valve on the PEX adapter so that it opens toward the fill valve.
12. Put the 3/8" compression nut on the PEX adapter so that it opens toward the compression fitting.
13. Slide the plastic ferrule onto the PEX adapter so that the skinny side is toward the compression fitting.
14. Slide the PEX adapter into the compression fitting and tighten the compression nut until the PEX adapter no longer moves in the compression fitting. I took a picture of it as it is the only semi complex thing to assemble in the whole project, see below.
15. Thread the 7/8" nut onto the bottom of the fill valve.
16. The top is adjustable on the unit I used, so adjust it to the desired water height.
17. I used a zip tie to tie the rubber hose that comes off the side of the fill valve so that it runs down parallel to the assembly instead of shooting strait out the side of the fill valve.

There you have it, an assembled portable automatic filler you can hook straight to a garden hose. Of course this setup might not be the ideal solution for everyone. I have made these a permanent fixture in a tank before as well. Which requires nothing more than drilling a 7/8" hole in the bottom of the tank and mounting the fill valve in the tank just as you would a toilet tank, then adapting it out to garden hose using the PEX adapter, the compression to 1/2" pipe adapter, a 1/2" pipe coupler, and a 1/2" pipe thread to garden hose adapter (a bit cheaper on parts, maybe a couple dollars, and requires no PVC primer or cement).