Slide-in backflow flap / internal non-return flap Nominal width 100 mm to 200 mm Opens smoothly, low pressure loss Closes securely, no noise, no rattling The damper is inserted into the ventilation duct For vertical and horizontal installation Housing: Galvanised steel Damper blade: Aluminium Shaft and spring: Stainless steel The non-return damper is used in round ventilation ducts to prevent air backflow. The casing is made of galvanised sheet steel. The damper blades are made of aluminium, the shaft and spring are made of stainless steel. The internal rubber seal reduces noise. The outer foam strip provides a good seal and secures the non-return flap in the pipe. The non-return damper is designed for operation at ambient temperatures up to 60°C, for the transport of clean air, free of coarse dust, grease, chemical vapours and other impurities.

Intelmann® Check Valve Ø 100–200 mm – Backflow Valve with Nipple Connection, GalvanisedThe Intelmann® Check Valve / Backflow Valve is the reliable solution for preventing air backflow in ventilation systems. It is installed between two ventilation pipes and simultaneously serves as a connector (nipple connection on both sides).Thanks to the particularly smooth flap mechanism, the valve opens with minimal airflow and ensures a low pressure loss. When stationary, it closes securely and silently, without rattling or disturbing noises.The housing is made of galvanised steel sheet, while the valve flap is made of aluminium. Shaft and spring made of stainless steel guarantee a durable and reliable function.Advantages at a glance:✅ Prevents air backflow – Reliable backflow prevention✅ Nipple connection on both sides – Connects two ventilation pipes✅ Smooth operation – Opens with minimal airflow✅ Low noise – No rattling when closing✅ Low pressure loss – Efficient air guidance✅ Flexible installation position – Suitable for vertical and horizontal installationTechnical details:✔ Product name: Intelmann® Check Valve / Backflow Valve✔ Diameter: Ø 100 – 200 mm✔ Length: 90 mm✔ Connection: Nipple connection on both sides (pipe connector)✔ Housing: Steel, galvanised✔ Valve flap: Aluminium✔ Shaft & spring: Stainless steel✔ Installation: Between two ventilation pipes✔ Installation position: Horizontal and vertical possibleInstallation instructions:The check valve is simply inserted between two spiral seam pipes and simultaneously serves as a connecting piece. Additional fixation can be done if necessary with sheet metal screws or sealing material.Application & areas of use:The check valve is used in ventilation and exhaust systems to prevent undesired air backflow. Typical applications include kitchen exhaust, bathroom ventilation, and general ventilation systems.With the Intelmann® Check Valve with Nipple Connection, you receive a compact, efficient, and installation-friendly solution for the safe operation of your ventilation system.

Stainless steel non-return flap with seal Ø 100 mm, l = 130 mm Non-return flap made of stainless steel 1.4301 (V2A), with seal made of EPDM material. For inhibiting backflow. The non-return damper is suitable for connecting spiral ducts with a diameter of 100 mm. Horizontal and vertical installation. The labelling must be observedduring installation.

Slide-in backflow flap / internal non-return flap Nominal width 100 mm to 200 mm Opens smoothly, low pressure loss Closes securely, no noise, no rattling The damper is inserted into the ventilation duct For vertical and horizontal installation Housing: Galvanised steel Damper blade: Aluminium Shaft and spring: Stainless steel The non-return damper is used in round ventilation ducts to prevent air backflow. The casing is made of galvanised sheet steel. The damper blades are made of aluminium, the shaft and spring are made of stainless steel. The internal rubber seal reduces noise. The outer foam strip provides a good seal and secures the non-return flap in the pipe. The non-return damper is designed for operation at ambient temperatures up to 60°C, for the transport of clean air, free of coarse dust, grease, chemical vapours and other impurities.

Stainless steel non-return flap with seal Ø 125 mm, l = 130 mm Non-return flap made of stainless steel 1.4301 (V2A), with seal made of EPDM material. To prevent backflow. The non-return flap is suitable for connecting spiral seam pipe with a diameter of 125 mm. Installation horizontal and vertical. When installing, the marking must be observed.