>You need to change filters at least once a year to keep your indoor climate good. It really depends on the location and on the specific machine/install, usual

>You need to change filters at least once a year to keep your indoor climate good. It really depends on the location and on the specific machine/install, usually there is no need to change the filters (they are normally washable) but they should be cleaned much more often, like every 6 (or even 3) months.