I have "older" Hardie automatic valves in my system, underground in a box, fed by a separate anti-siphon valve, 3/4 inch pipe. My problem is that one of the valve buzzes VERY loud when it is operating. I took it apart, cleaned all the sealing surfaces, and replaced the diaphram with no help. Wondering if the solenoid is bad and if that is what's buzzing? Not much else to replace from the looks of it so I'm confused. The valve turns on and off ok, but if the buzzing is bad enough, it reduces the ...
