Originally Posted by MEXANDME
It is a RB 1" DVF.
I have opened and closed the flow control and bleeder screw but I have not taken the valve apart. (I will have to dig up a large valve box to get to it.
4 valves in a 12x18 box.)
I've had DV's where the diapraghm had swollen over time and was restricting the flow through it. Kinda like Peter said the Irritrol 205 will.