Grant Combi/Euroflame/Multi Pass/Vortex Boiler Auto Air Vent (AAV) MPCBS29 Genuine Part - Hanicks It operates using a float mechanism—as air builds in the system, the float drops, opening the vent to expel air. Water then pushes the float back up to close the vent The Grant MPCBS29 is an automatic air vent (3/8" BSP male) used in sealed Grant heating systems. It automatically releases trapped air to prevent airlocks and circulation issues This part fits a wide range of Grant oil-fired boiler models, including but not limited to: Vortex Pro (internal & external) Vortex Eco (wall-hung, utility, condensing) Combi models such as Combi V3, Combi MKII, and others Euroflame and Multipass series Multipass Kitchen, etc The unit is made from corrosion-resistant brass, designed for durability Summary Grant MPCBS29 is a genuine automatic air vent for Grant oil-fired boilers. It helps maintain proper water circulation and prevents common issues like airlocks and cold radiator spots. Comes with manufacturer guarantee and is compatible with an extensive list of Grant boiler models., Manufacturer: Hanicks