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Honeywell 22mm Automatic By-pass Valve DU145B

Availability: In stock

The DU145 Automatic Bypass Valve controls flow of water through a bypass circuit which is installed between flow and return pipework, typically at or near the boiler. Building Regulation advice states that if a bypass is installed, an Automatic Bypass Valve must be fitted.

The DU145 saves energy by only allowing flow through the bypass when needed i.e. when flow through the system is reduced when zone valves or radiator thermostats are closing. The use of an ABV is recommended by the UK government as Best Practice in the CHeSS (Central Heating System Specifications) guide to central heating systems.


  • Unique and simple adjustment mechanism

  • High capacity flow - up to 50 litres per minute

  • Wide differential pressure range 0.1 to 0.6 bar

  • 22mm compression fittings for ease of installation

  • Reduces system noise and maintains an even system pressure

  • Ensures constant flow through boiler

  • Lockable set pressure prevents inadvertent adjustment

Honeywell Controls Ltd
1 Year
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