A cartridge for an aerosol-generating system, the cartridge comprising: a cartridge body comprising a cartridge main body and a cartridge cap configured to connect to the cartridge main body; and a fluid-permeable heating element disposed within the cartridge body, covered by the cartridge cap; wherein the cartridge body comprises at least one cartridge air inlet formed in the cartridge cap, and at least one cartridge air outlet; and a cartridge airflow path extending from the at least one cartridge air inlet to the at least one cartridge air outlet, via the fluid-permeable heating element; wherein the cartridge cap comprises Z r a threaded member disposed therein, the threaded member being configured to move within the cartridge body between: a first position, in which the threaded member blocks air from the cartridge air inlet from flowing to the cartridge air outlet, via the fluid-permeable heating element; and a second position, in which the threaded member is spaced away from the heating element to define an airflow path from the cartridge air inlet to the cartridge air outlet, via the fluid-permeable heating element; and wherein the threaded member is configured to move between the first and second positions by way of a threaded engagement between an outer threaded surface of the threaded member and a corresponding threaded inner surface on another part of the cartridge cap. a cartridge body comprising a cartridge main body and a cartridge cap configured to connect to the cartridge main body; and a fluid-permeable heating element disposed within the cartridge body, covered by the cartridge cap; wherein the cartridge body comprises at least one cartridge air inlet formed in the cartridge cap, and at least one cartridge air outlet; and a cartridge airflow path extending from the at least one cartridge air inlet to the at least one cartridge air outlet, via the fluid-permeable heating element; wherein the cartridge cap comprises Z r a threaded member disposed therein, the threaded member being configured to move within the cartridge body between: a first position, in which the threaded member blocks air from the cartridge air inlet from flowing to the cartridge air outlet, via the fluid-permeable heating element; and a second position, in which the threaded member is spaced away from the heating element to define an airflow path from the cartridge air inlet to the cartridge air outlet, via the fluid-permeable heating element; and wherein the threaded member is configured to move between the first and second positions by way of a threaded engagement between an outer threaded surface of the threaded member and a corresponding threaded inner surface on another part of the cartridge cap. a first position, in which the threaded member blocks air from the cartridge air inlet from flowing to the cartridge air outlet, via the fluid-permeable heating element; and a second position, in which the threaded member is spaced away from the heating element to define an airflow path from the cartridge air inlet to the cartridge air outlet, via the fluid-permeable heating element; and wherein the threaded member is configured to move between the first and second positions by way of a threaded engagement between an outer threaded surface of the threaded member and a corresponding threaded inner surface on another part of the cartridge cap.