Honeywell Straight Auto By-Pass Valve 22mm

Honeywell DU144A1001 Straight Auto By-Pass Valve 22mm controls the flow of water through a bypass circuit which is installed between flow and return pipework, typically at or near the boiler. Building Regulations advice states that if a bypass is installed, an automatic bypass valve must be fitted. The DU144 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.