Long Shank Return Valve

A Long Shank Return Valve is a specialized check valve variant designed to prevent the backflow of fluid in hydronic heating or cooling circuits, such as underfloor heating systems or radiator loops. Its primary function is to ensure unidirectional flow, allowing heated or cooled water to circulate in the intended direction while automatically closing to block any reverse flow that could disrupt system balance and efficiency. The defining "long shank" design features an extended valve body, enabling installation directly into a manifold port or deep-set connection point. This provides a secure, integrated fit and facilitates easier access for maintenance, making it essential for maintaining hydraulic separation and consistent thermal performance in modern HVAC systems.

Product Feature and Application

Long Shank Return Valves feature an elongated body designed to facilitate the return flow of fluids in recessed or insulated systems. Their primary feature is the extended reach, which allows for secure installation through thick partitions while keeping the adjustment port accessible. They are widely applied in underfloor heating manifolds and solar thermal circuits, where they regulate the return of water to the heat source, ensuring balanced pressure and optimal thermal efficiency across the entire loop.

Product Parameter

Technical Specification

Nominal Pressure: 1.6 MPa

Working Medium: Water

Operating Temperature: -10 °C ≤ T ≤ 100 °C

Thread conforms to ISO 228 standard

Female-Female Thread

Male-Female Thread

Installation Guidelines

1.Clean and prepare the piping system thoroughly before installing the valve.

2.Before installation, remove any protective end caps and inspect the valve ports and seating surfaces to ensure they are clean.

3.Provide adequate support for the valve to avoid stress from connecting piping.

4.Confirm that the valve’s pressure and temperature ratings are suitable for the intended service conditions.

5.Before placing the valve into service, cycle it fully from open to closed to verify smooth operation.

6.After installation, check that the packing nut is properly tightened.

Operating Instructions

Long Shank Return Valves are manually operated. Turn the handle counterclockwise to open and clockwise to close.

Inspection and Maintenance

1.Routine inspection and preventive maintenance are generally not required, aside from occasional adjustment of stem packing and periodic cycling of the valve from open to closed.

2.If a packing leak occurs, tighten the packing nut clockwise by about a quarter-turn—or until leakage stops—to increase sealing pressure on the stem packing. Never repack a valve while it is under system pressure.

3.When replacing the valve stem, also replace the packing material.