I definatly believe in installing inline valves and a seperate backflow device...for reasons that were hit on the dot in previous posts.....eventually valves fail, tear inside, or breakdown, and if the backflow you are relaying on in the valve fails then you will have a huge problem with series consequences. I would install inline valves (Irritrol 2400T Preferred) and a Febco or Watts Pressure Vacuum Breaker or Double Check! [
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