big problem. im working at a home with a large irrigation system. when the system turns on or switches zones, it causes the swing check on the cold feed to the water heater to chatter very loudly. the heater has a check valve because there is a hot water recirculation loop. if i close the ball valve to the tank the irrigation works quietly. would a ball check with a hammer arrestor and an expansion tank help. there is no exp tank after the check valve now but i will ad one to prevent the relief from popping anyway. any ideas would be helpful thanks.