http://www.LandscapingUniversity.com Install Backflow Connecting to Main Okay, so we're going to look at installing a backflow preventer. Once again, check your local laws and regulations on plumbing. Sometimes this is a phase that a licensed plumber needs to do, but every city and state code if different. In our case, we need a backflow preventer. Some need a more complicated backflow preventer, more sophisticated. Ours is a fairly simple requirement, so we want to go ahead and put a brass backflow preventer in. This is a threaded backflow preventer, so we're going to tighten our threaded fittings into each side. Make sure they're fairly tight. You don’t necessarily have to put these in a vice to tighten them because you can actually break the pipe by doing that. So as long as you are putting the Teflon tape onto the threads and tightening it fairly tight, you should be fine. And this is what's going to our main waterline. So once you've got it taped and tightened, then we're just going to glue those fittings right on to the Schedule 40 PVC. Once again, always clean before and glue next, once the cleaner is dry. So I’ve got an opened end on one end to let the plumber attach that right into our main line. And don’t forget to always check your direction. There should be an arrow on your backflow preventer to tell you which direction the water flow is meant to go. And that's backflow preventer. Now I’m just going to show where we're going to connect into our main water line. And our licensed plumber has made our connection for us.