It should be changed once every three months, or every four bags. The exhaust filter, which could be either the Miele Active AirClean SF-AA50 Filter or the Miele HEPA AirClean SF-HA50 Filter, should be changed once every 50 hours of use.
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It should be changed once every three months, or every four bags. The exhaust filter, which could be either the Miele Active AirClean SF-AA50 Filter or the Miele HEPA AirClean SF-HA50 Filter, should be changed once every 50 hours of use.