A device for small solid fuel firing systems for filtering fine dust, condensate and/or condensate constituents with a suction unit comprising - a connecting pipe for connecting the suction unit to a flue gas path from which a flue gas flows from a furnace, and - a suction opening, and a filter unit comprising - an inlet opening connected to the suction opening of the suction unit by means of a first connecting unit, - an outlet opening, - a filter element arranged between the inlet opening and the outlet opening, comprising a pre-filter and a fine filter following the pre-filter in terms of flow, and - a fan arranged between the outlet opening and the filter element, which is set up to generate an intake pressure, wherein the suction unit and the filter unit are arranged spatially separated from one another as separate assemblies and are connected or can be connected to one another by means of connecting units or means (38, 48), wherein the filter element of the filter unit, comprising a pre-filter and a fine filter, can be regenerated or is regenerated in the installed state within the filter unit by mechanical movement of the filter element of the filter unit by vibration, tapping or shaking or pneumatically by pressure surge or compressed air surge by means of a device wherein the filter element for the pre-filter is a depth filter for separating fine dust, condensate and/or condensate constituents in accordance with filter class G4, M5 or M6 in accordance with DIN EN 779 and the filter element for the fine filter is a depth filter for separating fine dust, condensate and/or condensate constituents in accordance with filter class F7 to F9 in accordance with DIN EN 779. a suction unit comprising - a connecting pipe for connecting the suction unit to a flue gas path from which a flue gas flows from a furnace, and - a suction opening, and - a connecting pipe for connecting the suction unit to a flue gas path from which a flue gas flows from a furnace, and - a suction opening, a filter unit comprising - an inlet opening connected to the suction opening of the suction unit by means of a first connecting unit, - an outlet opening, - a filter element arranged between the inlet opening and the outlet opening, comprising a pre-filter and a fine filter following the pre-filter in terms of flow, and - a fan arranged between the outlet opening and the filter element, which is set up to generate an intake pressure, - an inlet opening connected to the suction opening of the suction unit by means of a first connecting unit, - an outlet opening, - a filter element arranged between the inlet opening and the outlet opening, comprising a pre-filter and a fine filter following the pre-filter in terms of flow, and - a fan arranged between the outlet opening and the filter element, which is set up to generate an intake pressure, wherein the suction unit and the filter unit are arranged spatially separated from one another as separate assemblies and are connected or can be connected to one another by means of connecting units or means (38, 48), wherein the filter element of the filter unit, comprising a pre-filter and a fine filter, can be regenerated or is regenerated in the installed state within the filter unit by mechanical movement of the filter element of the filter unit by vibration, tapping or shaking or pneumatically by pressure surge or compressed air surge by means of a device wherein the filter element for the pre-filter is a depth filter for separating fine dust, condensate and/or condensate constituents in accordance with filter class G4, M5 or M6 in accordance with DIN EN 779 and the filter element for the fine filter is a depth filter for separating fine dust, condensate and/or condensate constituents in accordance with filter class F7 to F9 in accordance with DIN EN 779.