Patent ID: 7468084

Claim:
A device for conditioning recirculating clean room air, the device comprising: at least one filter fan unit mounted on a ceiling of a room and arranged in a common plenum above the ceiling, wherein the at least one filter fan unit comprises a housing, a fan and a filter, wherein the fan and the filter are arranged inside the housing; at least one return air conduit through which a first portion of recirculating clean room air is supplied from a bottom area of the room to the common plenum and from the common plenum is sucked in by the fan into the at least one filter fan unit; wherein the fan has at least one intake that opens into the room at the ceiling; wherein a second portion of the recirculating clean room air bypasses the at least one return air conduit and is directly supplied to the fan through the at least one intake; wherein the at least one intake is an intake line connected to the housing of the at least one filter fan unit or the at least one intake is integrated into the housing of the at least one filter fan unit.