I have a planting bed with 100' of drip irrigation tubing that I'm running off a hose bib. Our house is on a well, so I'm not dealing with a municipal water supply. I have a brass vacuum breaker on the hose bib per our local code, and I have another so-called "back-flow preventer" (looks like just another vacuum breaker, except plastic) that screws onto the the brass vaccum breaker to start the drip piping. It would be a major deal to plumb a real backflow preventer into the system because of the way the house is built. So that's not going to happen. But I want to make sure I'm doing everything I can short of that to prevent any potential siphoning. It seems from what I read that DIY drip systems are often supplied by a hose bib with vacuum breaker, but I also read warnings about relying on a vacuum breaker to prevent backflow with certainty. QUESTION: Do I need to be worrying about this or is my double vacuum breaker (brass vacuum breaker + drip irrigation system vacuum breaker) adequate? I've also read that an air gap would prevent any siphoning. What about this idea: The hose bib comes out of the wall and has the brass vacuum breaker attached to it. Then, with the necessary hose thread adapter, I attach a tee to the hose bib......one end of the top of the tee is attached to the hose bib and the other end of the top of the tee connects (with the proper adapter) to the drip irrigation's plastic vacuum breaker, pressure reducer and piping. I attach a ball valve to the leg of tee. Now ,when I am ready to turn off the water after irrigating, before I turn the handle on the hose bib to close the valve, I open the ball valve attched to the tee. NOW I turn off the water. With the ball valve open, I'm thinking any possible back-flow that makes it past the plastic irrigation system vacuum breaker, would exit out that ball valve before reaching the second (brass) vacuum breaker on the hose bib.
I'd apprecaiate any feedback. Thanks.
I'd apprecaiate any feedback. Thanks.
