Pressure Reducing Valve

[loafer]

I have small Watts reducing valve that is used to drop the pressure to 15psi on a conditioning chamber. The problem I have is the valve will not hold pressure. No matter what I set it to, the pressure slowly increases until it reaches full supply pressure. I replaced the valve with a new one, and it does the same thing. My supply water pressure fluctuates significantly between 40 - 65 psi due to another piece of equipment that overwhelms the building water supply. I've contacted Watts and the equipment manufacturer that installed the valve originally. They have no ideas. Anyone come across an issue like this before? Do you think the supply pressure fluctuations could cause this?

 

[hj]

You are getting valves that will regulate a "flowing" liquid, but do not maintain pressure in a "dead head" situation. I don't know what you mean by "small" regulators, but the "larger" ones, i.e., 1/2" and larger, do not have that problem.