The Honeywell F115 commercial ceiling mounted media air cleaner is a self contained commercial air cleaning unit. It is typicaly used in a restaurant or bar where smoking is an issue. Normal maintenance is to replace the Honeywell F115A1064, F115A1171, F115C1005 and F115C1054 prefilters every month, the HEPA filter every 10 to 24 months and the CPZ filter every 4 to 12 months. Heavy smoking bars should use the more often version of those dates.