Back draft damper for insertion into 4 inch ventilation ducts. The backflow damper RKI opens and closes automatically. It has a strong spring and can be installed either horizontally or vertically. The flap is suitable for retrofitting, since it is completely inside the duct

A tight sealing and fastening of the duct is achieved by the rubber strip attached to the outside of the draft blocker damper. The rubber seal prevents loud rattling when the flap blades open and close. The housing of the flap is made of galvanized steel, the flap blades are made of aluminum, the axle and spring are made of stainless steel

Designed for use in AC, dryers, exhaust, extractor or range hoods, heating systems, vents and other residential, commercial and industrial HVAC applications

FUNCTIONALITY: Duct draft stopper prevent cold air or wind from entering the ventilation pipe. In this case, the flap is installed in such a way that the flap leaves only open into the outgoing air direction. This means that no (cold) air / wind can penetrate the ventilation pipe from the outside.

INSTALLATION: The backflow Preventer valve is installed by pushing it into the ventilation pipe as far as it will go. The position of the spring should be horizontal when the flap is installed horizontally so that it can be opened and closed optimally. This also applies to the vertical installation.