Caleffi 519566A Differential Pressure Bypass Valve 3/4" Press Connections for Hydronic Systems

The Caleffi 519566A is a 3/4" differential pressure bypass valve with 3/4" press connections, used to maintain minimum flow and limit differential pressure in hydronic systems with zone valves.

Installed between supply and return, the valve opens as zone valves close and system differential pressure rises, bypassing flow to protect the circulator and boiler and to reduce flow noise in the zones that remain open.

Before ordering: Confirm the 3/4" press connections suit your piping layout and press tool. Set the valve based on the circulator curve and system design; the setting procedure is in the installation manual below.

Specifications

• Brand: Caleffi
• Manufacturer Part #: 519566A
• Series: 519 series differential bypass valve
• Type: Differential pressure bypass valve
• Size: 3/4"
• Connection: 3/4" press
• UPC: 8016615471205
• Category: Balancing Valves

Documents

• Technical Data Sheet (PDF)
• Installation & Operation Manual (PDF)
• Submittal Sheet (PDF)
• Product Brochure (PDF)

See also: balancing valves, all Caleffi products.