Intended use

DRD H, DRD V, DRD HT and DRD HT 2V centrifugal roof fans are used for air extraction of residential, commercial or industrial buildings either directly or by means of ducts. DRD are used to convey air, which is clean to slightly dusty. Any other use or use that goes beyond this is considered improper use.

Operation of the DRD is only permissible:

• as a permanent installation on a roof with sufficient load-bearing capacity,
• with a roof socket suited to the DRD variant
  or mounted directly on a flat roof,
• in a horizontal installation position on the fan roof flashing,
• with a flexible cuff fitted if there is a duct connection between DRD and a folded spiral-seams duct/ventilation channel,
• with permanent electrical installation,
• with protection against accidental contact in accordance with EN ISO 13857, e.g. with SGR protective grille, fitted if there is a free inlet.