I have an Enviracare F300 air purifier attached to my furnace. It has a built in ( wire mesh) prefilter as well. There is no filter in the intake grill in our hallway though.... should there be one in addition to the air purifier or was it removed because it is no longer needed
Last edited by beenthere; 02-16-2012 at 03:58 PM.
Reason: Remove link to another DIY forum