Determine theparameters by
measuring the inlet pressure. Choose the outlet pressure you require,
which should typically be in the range of 50 to 70 psi for domestic
applications. Decide on the minimum and maximum flow rates you need to
maintain in gallons per minute or liters per minute.
 Consider the inlet water pressure.
Pressure regulating valves can be direct acting, piston operated or
externally piloted models. Choose direct acting valves for flows ranging
from low to moderate. For moderate to high flow rates, use piston
operated or externally piloted pressure reducing valves.
 Choose the right valve size needed. Choosing the right size is
critical to the longevity of the pressure reducing valve. Over-sized
valves will lead to noise, valve failure and wire draw during low flow
conditions. If more than one size of valve meets your required capacity,
choose the valve that is less expensive and allows you to use smaller
diameter pipes.

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