CL600 Exhaust Air System


High extraction rate at minimum energy consumption
The Big Dutchman CL 600 air exhaust system is used for extraction of air from livestock houses. Its aerodynamic design leads to high performance with low energy consumption.

The built-in fan, which has been specially developed for the CL 600 chimney, ensures an optimum ratio of pressure stability and energy consumption. Fans are controlled either on/off or according to the speed required.


    • The chimney has a 650 mm or 25.5” diameter
    • It is made of polypropylene with a smooth, dirt-repelling surface
    • Insensitive to sunlight and frost.
    • Can be easily cleaned with a high-pressure cleaning system.


    • By altering radial and circular flow components, the exhaust air jet is concentrated, leading to a significantly increased working range (of up to 80 %)
    • There is only a minimal decrease in exhaust-air performance of the chimney (approx. 3 %)
    • The chimneys do not have to be elongated, so storm bracings are not necessary
    • Cost-effective alternative compared to chimney elongation
    • Quick and easy assembly


    • Labyrinth seal between roof duct and roof sheet prevents water from entering into the roof area
    • Exhaust air cone increases the exhaust air rate (Venturi effect) and keeps away most of the rain
    • Roof duct for the connection between cone and roof sheet
    • Built-in fan ensures an optimum ratio between pressure
    • Specially-shaped suction head for increased exhaust air performance


    • The damper, mounted inside the suction head of the chimney, is used as the chimney shutter or for reducing the volume of air.
    • The chimney damper can either be adjusted centrally by a winch or individually by using a CL 74 servo motor mounted directly to the shaft of the damper.
    • The air extraction rate of each chimney can be controlled individually – for example by applying the MultiStep® control concept.


MultiStep® is an exhaust air extraction concept applying a combination of variable control and group control. The climate computer regulates the system by controlling one chimney on an infinitely variable, 0-100 % basis and switching additional chimneys on or off at full power as required. MutiStep enables you to increase air rate and cut down energy consumption. Compared to traditional negative pressure systems, MultiStep can lower annual power costs up to 60%.