For use on hot or chilled water.

Description

The VS-41 differential pressure regulating valve is used to limit the differential pressure of reverse return and other types of water systems controlled by 2-way contol valves.

As the control valves in a building close, the water circulation in the building becomes choked off and the differential pressure across the valves increases to the point that the valves hiss or whistle, the valve internals can become damaged. Modulating control becomes difficult or impossible to achieve.

The usual corrective action is to:

1. Reduce the water temperatures during mild weather so that the control valves open wider and modulate better.

2. Reduce the differential pressure by one of several methods (see Spartan publications "Valve Selection Guide" and " Control of Building Differential Pressures on Building Risers").

3. Supply 3-way control valves with bypass instead of 2-way control valves.

These VS-41 regulators offer the advantage of controlling the pressures where the pressure in important. Usually, a large bypass valve controlled by a differential pressure regulator is installed across the circulating pump. They reduce the differential pressure for the entire building.

VS-41 regulators are installed in the reverse return loops, one per floor. In this way, the differential pressure is controlled at the respective loop, the riser differential pressure remaining untouched and able to pump to other floors or areas.

VS-41 regulators are less costly, easier to install, more accurate (controlling zones rather than the entire systems), being easier to adjust, simple and self-acting and suitable for new installations or retrofit economically.

VS-41 regulators come in two ranges:

• VS-4110: 0.15 to 0.7 bar or 2 to 10 psi.
• VS-4120: 050 bar to 1.00 bar or 10 to 20 psi.