|
Not that this is the most likely problem, but it could just be a cheap, barely functional pressure reducing valve which vibrates when it works ...errr sort of works. There is a spring inside these devices and if the valve is not properly designed, the spring can allow the internals to vibrate at certain flow rates.
Even if it is a good design, if it is not sized properly for the flowrate, it could vibrate. It could be too big for your flowrate and since the valve plug is then too close to the valve seat, it is much more likely to vibrate. If possible, while it is vibrating try to substantially increase the flow of water, if not from the drip nozzles themselves then create additional flow somehow after the regulator. If the vibration stops, that's an indication that it could be too large for the drip flow.
If the reducer is adjustable, try different pressure settings and quite likely a higher or lower pressure will stop the vibration.
|