1. Choose: In case you want to replace the G3 coarse filters more often than the F7 cassette filters, add two extra coarse filters to your order by choosing: Filterset + 2 extra pcs of G3 coarse filters.
The recommended interval for filter changes is 2–3 times a year. In connection to the filter change, clean the ventilation unit and remove possible loose dirt, for example by using a vacuum cleaner. You should also check the condition of the heat exchanger and clean it if necessary with suitable detergent.