Bypass valves are normally used on delivery piping to transfer part of the fluid when the flow is interrupted by one of more motorised and/or self-operated shut-off valves (thermostatic valves, zone and two-way control valves, etc.). The bypass valve eliminates the risk of a gradual increase in speed of the fluid in open utilities and, at the same time, avoids wear and excessive vibrations and noise.
The valves are calibrated by turning the control knob to loosen the compression spring. The differential pressure can be set to a maximum of 0.7 bar. The values are shown on a slide with markers (e.g. 0.7 = 70 kPa).
The calibration value must be equal to the sum of the pressure drops between the point where the valve is located and the terminal at the least convenient distance.
In the case of systems with more than one distribution zone, it is advisable to install several bypass valves for the purpose of a more sensitive adjustment.
The bypass valves are available in the 3/4” – 1” – 1”1/4 sizes for
iron pipes and in the version with Ø22 connections for copper
The bypass valves are to be installed:
- Between the uprights for primary distribution;
- On the primary distribution manifolds.