ABBV1-C Auto Bypass

Auto Bypass Valve

The Corgi ABBV1-C should be fitted where a boiler bypass is required – typically this is the case when a system is equipped with thermostatic radiator valves (TRV’s), and to allow pump overrun operation after zone valves have closed down.

TRV’s slowly close down as each radiator raises the room temperature. To overcomeflow restriction as TRV’s close down, the ABBV1-C is adjusted to the required set point. As the system resistance increases due to TRV’s closing, the ABBV1-C allows flow to increase, in order to maintain the required pre-set system differential pressure. The regulation provided will reduce system noise that can result from TRV’s or zone valves closing, eliminate pump impeller wear that can result from high flow resistance, and enhance the life of the boiler’s heat exchanger by ensuring minimum flow rate at all times.


  •  Regulates heating system differential pressure
  • High capacity flow, up to 50 litres per minute
  • Differential pressure range 0.1 to 0.6 bar
  • 22mm compression fitting
  • Reduces system noise
  • Lockable set pressure
  • Constant flow through boiler

Code: ABBV1-C