These optional filters should later be removed and discarded during the balancing and commissioning process. Operating units after construction with filters in place is not recommended. Fan-powered units, like all terminal units, are designed for zero maintenance. This is necessary because terminal units, unlike air handlers, are typically located above finished ceilings in tenant spaces. Accessing the units regularly to change filters can be nuisance to tenants, time-consuming for maintenance personnel and can easily result in ceiling damage.
If filtering of return air is desired, we recommend the installation of filter grilles in the ceiling. This allows the building and the building owner the benefits of less costly standard filter sizes; more filter area for longer service intervals and quicker access for easier replacement.
Randy Zimmerman ~ Chief Engineer