Differential valve for central heating FERRO ZR2 5/4" for CO systems

FERRO ZR2 differential valve for central heating with a 5/4" connection is designed to balance pressure differences and stabilise flow in closed CO heating circuits. The valve reduces hydraulic disturbances caused by simultaneous pump operation or zone control, helping maintain steady flow through radiators, underfloor heating manifolds, and boilers. Constructed for residential and light-commercial systems, the device is intended for use where reliable differential pressure control is needed to secure efficient heat distribution.

Advantages

The differential valve provides smooth pressure equalisation across heating branches, which minimises unwanted flow noise and prevents thermal imbalance between radiators. Its robust construction and compatible 5/4" connection make it simple to integrate into existing piping layouts. By reducing the risk of hydraulic interference, the valve supports consistent boiler operation and can improve system stability over a wide range of flow conditions.

Suitable for

• Residential central heating systems with multiple heating circuits
• Light-commercial buildings requiring stable pressure control
• Systems with radiator groups, underfloor heating manifolds, or thermostatic valve clusters
• Installations where pump staging or zone valves cause pressure fluctuations

Key specifications

• Connection size: 5/4" (threaded)
• Function: differential pressure regulation for central heating circuits
• Application: closed water-based heating systems (CO)
• Material: corrosion-resistant valve body suitable for heating media
• Installation orientation: inline with primary/secondary circuit piping

How to use

Install the differential valve in the return or supply line where pressure variations occur, following local plumbing codes and the system design. Ensure appropriate shut-off valves and strainers are fitted to allow maintenance. Commission the system by gradually increasing pump speed or opening zone valves while observing flow and pressure; the valve will self-regulate differential pressure within its operational range. Regular inspections during scheduled maintenance help confirm correct operation and detect debris or signs of wear.

Usage recommendations

For optimal performance, fit the valve together with isolation and flushing fittings to allow system cleaning before commissioning. Use compatible pipe materials and ensure correct thread sealing. When integrating with pump controls or multiple zones, verify settings on pump staging devices to avoid exceeding the valve’s intended differential pressure range.