Worcester Highflow 400 BF OF RSF 22mm Return Isolating Valve 87161424340

Product Overview

The Worcester Bosch Highflow 400 Return Isolating Valve (Part Number: 87161424340) is a 22mm hydraulic isolation component designed for selected Worcester Bosch boiler systems.

The valve forms part of the boiler's central heating return circuit, allowing the relevant water connection to be isolated when required for servicing or maintenance.

Its purpose is to provide controlled isolation of the heating return connection while maintaining a secure water pathway during normal operation.

Correct valve operation and sealing are important for maintaining the integrity of the boiler's hydraulic system.

ℹ️ Product Condition Options:

This part may be available in New or Refurbished condition. Please select your desired option from the dropdown menu above. Refurbished valves should be professionally inspected and tested for correct operation and leakage before installation.

Technical Insight & Common Failure Symptoms

The 22mm return isolating valve is a mechanical shut-off component within the boiler's central heating hydraulic system.

It allows the heating return connection to be isolated for appropriate servicing operations without acting as an automatic pressure regulator or water-flow control device.

Over time, isolating valves may be affected by mechanical wear, corrosion, internal deposits or deterioration of sealing components.

Possible symptoms that may indicate an isolating valve or associated hydraulic connection problem include:

• Water leakage around the valve body or connections.

• Valve failing to open or close correctly.

• Valve mechanism becoming stiff or difficult to operate.

• Visible corrosion or deterioration.

• Damaged or worn sealing surfaces.

• Heating system pressure loss associated with leakage.

• Valve failing to provide effective isolation when closed.

These symptoms do not necessarily confirm a faulty isolating valve, as similar problems may result from damaged seals, pipe connections or other hydraulic components. Correct professional diagnosis should be carried out before replacement.

Compatibility

This part (MPN: 87161424340) is associated with selected Worcester Bosch Highflow 400 BF, OF and RSF boiler systems, including relevant natural gas and LPG variants.

Please verify the exact boiler model, GC number, part number, 22mm connection specification and valve arrangement against the manufacturer's technical documentation before ordering to ensure correct fitment.

Safety Advice

Boiler isolating valves and associated pressurised hydraulic components should only be inspected, removed or installed by a suitably qualified and competent heating engineer.

Always isolate the appliance and allow the heating system to cool before carrying out any work. The relevant water circuit must be safely isolated and depressurised before removing the valve. Follow the manufacturer's servicing instructions and complete all required pressure, leakage and operational safety checks before returning the boiler to service.