Cost of replacement filters: Like a normal rule, you should change filters (or clean All those that can be vacuumed) each six to twelve months When they are pleated and each a few months for activated carbon filters. A lot of the models we check have an indicator light that https://bookmarkpagerank.com/story16968544/the-fact-about-air-purifier-dyson-review-that-no-one-is-suggesting