Best Backflow Preventer Installation in Irvine CA

The fire line in my garage makes a clicking sound every day at the same time, which bothered me for a long time. I contacted California fire protection and explained that problem. They analyzed it and provided very helpful information for free!  It turned out the irrigation system caused it, and I need a plumber to install a check valve. Thanks a lot!!!

Had a backflow on my property for years and it wasn't​ until recently that I was mandated by the city to have it inspected. I called one flow and spoke to John who happened to be the owner. After a brief conversation on backflows, he realized he wasn't too far from my property and told me he could stop by after his current appointment. Upon arriving he gave me a crash course on the device and the importance of testing backflows. He then gave me a quote before any work was done (a real rarity with contractors). John provided​ Great customer service and provided testing the same day I​ called​! I will be using john and one flow for all my backflow needs in the future!