The aerosol generating system (10) comprises a heater assembly (24) and a manually operated pump (20). The pump comprises a hollow member (30) with an inlet portion (32) and an outlet portion (34), wherein the inlet portion of the hollow member is configured to be connected with a liquid storage portion (18), the outlet portion of the hollow member is in fluid connection with a dispensing assembly (22). The pump is configured for dispensing the liquid aerosol-forming onto the heater assembly, and operable to pump a liquid aerosol- forming substrate from the liquid storage portion via the dispensing assembly onto the heater assembly.
