Homemade Anti-siphon Check Valve (zip-tie + latex glove)

A tale about bootstrapping your startup.

The weather lately has been super rainy, which unfortunately comes with some water in our basement. After our sump pump broke down I was able to switch in a utility pump and move the float-switch from the sump pump to that and it worked well.

The one problem I had, though, was that the utility pump uses a standard garden hose and neither I, nor my local hardware stores, had an attachment to make it not siphon when it wasn't running.

What this means is that once the utility pump emptied the well it is in and switched off, all the water that was in the hose would flow back down and fill the well half way back up. Obviously this means that half the work the utility pump was doing was put into moving that half-well of water back out. Basically it was working twice as much as it needed to.

I put up with this for a bit, but it stayed in the back of my head because this is a problem that should be solvable.

Today I hit upon it - using a latex glove to block the end of the hose when the water stopped so that air couldn't enter the end of the hose and let the water flow backward.

Here's the recipe:

1. cut the tips off all the fingers of a latex glove, except the middle finger;
2. put the latex glove over the hose with the end of the hose down as far into the middle finger as you can get it;
3. stretch it fairly tight and ziptie the wrist of the glove around the hose to hold it in place.

I'm mainly posting this because I didn't have much luck searching for homemade solutions online. So maybe this method will catch on. Just sent me a $1 royalty any time you use it. ;-) My guess is the "parts" probably total about $0.05 in cost.

Here's what happens. When the water turns on, the pressure expands the middle finger part and the water flows up and out the other fingers. When the water stops, the lack of pressure lets the glove contract back into place, with the middle finger back around the hose. When the water wants to flow backward in the hose, the negative pressure sucks the tip of the middle finger back into the hose where it forms a tight seal around the end of the hose and stops it.

Of course, you could use duct-tape instead of a zip-tie - but I like to use zip-ties whenever possible.

Here's why this is better than store-bought! I was able to do this on the end of a hose that had been cut to length, with an irregular shaped end and no threads.

I just couldn't resist a little video to show clearly how it works. This is the one I did around the hose with the cut end. Yes, it is giving you the finger.

Direct link: here



The funny thing about this whole exercise is that it reminded me of what it's like bootstrapping a startup.

There's always a way to solve a problem. The solution you think of first you might not be able to get access to or afford. But remember that you may just have a latex glove and some zip-ties laying around that might even do the job better.