The Baxi flow pipe is designed for use with the System IE, Performa, Combi, Main Combi, or Combi HE and Main HE boilers. Pipework in a boiler either allows water or gas into a heating unit, such as the mains water supply and pipework on a wall jig, or is found within an appliance and transports water between the various mechanisms that require it, such as the diverter valve and heat exchanger.