The valve is installed in the bypass between the flow and return pipes and opens on rising differential pressure to allow flow through the bypass. This maintains the differential pressure between the flow and return pipes at the predetermined set value. Differential bypass valves are used in systems with variable flowrates.
Radiator circuits utilising thermostatic radiator valves or heating systems incorporating 2-port control valves are typical applications. Differential bypass valves can be used in both constant and variable volume systems to prevent the differential pressure from rising, which can seriously affect the performance of the 2-port control valves.
Series 519 differential bypass valves use a stainless steel compression spring to exert a predetermined force onto the disc. The force is adjustable by turning the control knob to set the required differential pressure between 1 to 6 m head, which corresponds to 10 to 60 kPa. The setting is then locked using the locking screw on the side of the control knob to prevent unauthorised adjustment.
1 Pipe Accessory Family with two types;
519500 ¾” screwed iron F x F – 10-60 kPa
519504 ¾” screwed iron F x F - 100-400 kPa
COBie and NBSCreate Parameters
Altecnic BIM Userguide