Duct restrictions at fans

Experts in Ventilation

Duct restrictions at fans

Ducts significantly smaller than the fan diameter create turbulence if transitions connect directly to fan.

Don't

An abrupt duct expansion at fan inlet causes air separation from the duct, starves the impeller tips, creates turbulence, reduces performance and generates increased noise.

Do

Duct expansions on the inlet to axial flow fans should be avoided where at all possible.
If essential the transition should have an included angle of not more that 15º

Propriety information courtesy of FANTECH (Australia) - (NOT TO BE REPRODUCED)

TDE

The Multiflow TDE 500 to 710 range consist of fully cased, cylindrical models with circular mounting flanges at both ends and a wired terminal box.

The Mini Centrifugal Roof Fan series are the new type roof extract units available in 2 sizes and suitable for vertical and horizontal installation. The low noise external motor and high efficient backward bladed impeller meets the requirement of efficient ventilation in residential, commercial and light industrial applications.

Future 150

The Decor Series can be wall or ceiling mounted and is designed to exhaust stale and moist air from bathrooms, toilets, laundries etc. They are also suitable for ventilating all types of small or closed areas.

TD Silent

The Silent Series is a low profile mixed-flow in-line fan that produces low noise when in operation. It does this through a specifically designed perforated internal skin that directs sound waves produced inside the fan to a layer of sound absorbent material.

TD-Evo

NEW!! TD-EVO

The low-profile TD-EVO 250 and 315 in-line mixed-flow fans for circular ducts have a unique design where the support bracket allows the motor and impeller assembly to be fitted or removed without dismantling the adjacent ducting.