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 and also known as a model 15000. Normal maintenance is to replace the Honeywell F115 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.