Helios Fans VDD 225/4 Ex

The Helios VDD 225/4 Ex is a high-efficiency centrifugal roof fan designed for vertical discharge in hazardous or explosive environments, certified according to ATEX standards. Its aerodynamic housing is made from seawater-resistant aluminium and includes integrated anti-intrusion protection for added safety.

The fan’s construction includes a galvanized steel base and motor support plate, with an aluminium inlet nozzle to ensure corrosion resistance. The base plate features a threaded screw on the intake side for accessory mounting and follows the hole pattern outlined in DIN 24155, sheet 3. A protective discharge-side grille is fitted as standard in compliance with DIN EN ISO 13857 safety regulations.

The unit is equipped with a backward-curved centrifugal impeller made from aluminium, which is dynamically balanced to DIN ISO 1940 – 1 standards to ensure quiet, vibration-free operation.

A totally enclosed three-phase external rotor motor (IP 44 rated) drives the fan. It is speed-controllable, mounted on ball bearings with moisture protection, and designed to operate maintenance-free and interference-free. The entire assembly is explosion-proof, making it ideal for industrial and commercial ventilation applications in ATEX-regulated environments.