Helios Fans RDD 225/4 Ex

The Helios RDD 225/4 Ex is a high-performance horizontal roof fan designed for use in hazardous areas requiring explosion-proof equipment. Certified to ATEX standards, it provides safe and efficient ventilation in industrial environments where explosive gases or dust may be present.

This roof fan features a corrosion-resistant, seawater-proof aluminum housing with integrated intrusion protection for enhanced durability. The motor support and base plates are constructed from galvanized steel and paired with an aluminum inlet nozzle. The base plate includes a threaded screw and standard hole pattern (DIN 24155, sheet 3) for attaching compatible suction-side accessories. A safety grille is pre-installed on the discharge side in compliance with DIN EN ISO 13857.

At the heart of the unit is a newly engineered radial impeller with backward-curved aluminum blades, optimized for performance and dynamically balanced to DIN ISO 1940 – 1 standards. The fan is driven by a speed-controllable, three-phase external rotor motor enclosed in an IP44-rated housing, offering protection against moisture and dust. The motor is ball-bearing mounted, maintenance-free, interference-free, and thermally protected — delivering reliable operation in explosive zones