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Honeywell 22mm Straight Automatic By-Pass Valve DU144

Item Code: DU144A1001


Quick Overview

The DU144 automatic bypass and differential pressure valve is used to maintain constant differential pressure in a heating system. It reduces flow noise in a system, particularly as thermostatic radiator valves are closing. The boiler return temperature is raised and this reduces the corrosion caused by flue gas condensation. In addition, when radiator valves are closed it also maintains flow over the temperature sensor on the boiler to ensure proper operation of external temperature compensating controls. On gas fired water heaters it guarantees a minimum flow circulation when thermostats or radiator valves are closed.


  • 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 x 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


Technical Details
  • 22mm Comperssion
  • Max. pressure : 10 bar
  • Max. temp. : 120°C
  • Δ P range : 0.1 to 0.6 bar
Size 22mm
Fitting Type Compression Brass


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This product appears in the following categories:  Valves

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