Adding the Sprinkler Magician system may, but not always, involve adding an RP type Backflow valve. It is important that you or your installer verify with your local and state ordinances to make sure your Sprinkler Magician is installed with the correct equipment. If you do have to upgrade, it is a relatively inexpensive and quickly added change to your irrigation system. Click Here to watch our video. And, as always if you have any questions you can always contact your local Authorized Sprinkler Magician reseller or Sprinkler Magician at 888-829-0893.