Vents VK 100 Duo R centrifugal fan Ø 100 MM

A 100 mm centrifugal duct fan with two speeds: 157 or 264 m³/h, selected with a thyristor two-speed controller.

The VK 100 Duo R is the two-speed version. That sounds like the same thing as an ordinary fan with a controller behind it, and it is not quite.

Two built-in speeds against one speed plus a controller

Almost any duct fan can be turned down with an external speed controller. The difference is in how the turning down happens.

A Duo model has a motor that can run on two windings: two speeds the motor was designed for, each with its own cooling and its own noise. You pick one, and on either it runs as intended.

An external controller instead chops the voltage or the waveform to make one motor run slower. That works, but it takes the motor outside its design point: at low settings it cools less well, and some motors start to hum or buzz.

For this version that means 157 m³/h on low and 264 on high, both speeds the motor is built for. The range is wider than the standard VK 100, which has a single 250 m³/h speed, so you get both a more economical night setting and a higher peak.

In practice you switch with the matching thyristor controller. Several fans on one controller is possible, as long as the total power stays within that controller's rating.

Build

Centrifugal impeller with backward-curved blades, dynamically balanced, asynchronous external rotor motor with self-resetting overheat protection and ball bearings for at least 40,000 hours. Corrosion-resistant plastic casing, IPX4, class II, and horizontal or vertical mounting.

Technical Specifications:

• Power draw: 45 W on low, 57 W on high
• Current: 0.21 A to 0.25 A
• Duct size: 100 mm
• Airflow: 157 m³/h on low, 264 on high
• Motor: two-speed, asynchronous external rotor
• Control: thyristor two-speed controller
• Protection: self-resetting overheat cut-out
• Bearings: ball, at least 40,000 hours
• Casing: corrosion-resistant plastic
• Ingress protection: IPX4, class II
• Mounting: horizontal or vertical

Frequently asked questions

Why not just a standard model with a controller?
You can, but the motor then runs outside its design point at low settings. A Duo has two real speeds the motor was built for.

Can I run two fans from one controller?
Yes, as long as total power and current stay within the controller's rating.

Does the high speed beat the standard VK 100?
Slightly: 264 against 250 m³/h. The gain is mostly in the 157 low speed.

Can it switch automatically on temperature?
Not this version. The U version with its built-in thermostat is the one for that.