Centrifugal Fan for Ducted Ventilation | Wisdo Merchants

Centrifugal Fan for Ducted Extract and Ventilation

Ordinary propeller fans move plenty of air in open spaces. Connect them to a long duct, though, and the airflow drops fast. Ducts, bends, filters and grills all push back against the fan. A centrifugal fan is built for exactly this job. It builds up pressure to push air through ductwork and still deliver strong airflow at the far end. At Wisdo Merchants, we supply centrifugal fans to HVAC contractors, kitchen fitters, factories and building maintenance teams across Nairobi and Kenya.

A centrifugal fan draws air into the centre of a spinning impeller. The blades then throw the air outwards into a scroll-shaped housing, which turns that speed into pressure. As a result, the fan keeps moving air steadily through long duct runs where an axial fan would struggle.

Features and Benefits of the Centrifugal Fan

• High pressure. It pushes air through long ducts, bends and filters without losing much airflow.
• Steady airflow. It keeps extracting reliably even as filters and grills collect dust.
• Duct-ready design. The flanged inlet and outlet bolt straight onto ducting.
• Versatile. It handles extract, exhaust, fresh air supply and air movement in AC systems.
• Heavy-duty build. A painted steel scroll housing on a rigid base frame handles long running hours in commercial and industrial settings.

For contractors, this means systems that deliver the airflow they were designed for. Meanwhile, building owners get fresher air, fewer smells and a more comfortable space.

Technical Specifications

Applications of the Centrifugal Fan and How to Use It

• Commercial kitchen extract with hoods and long ducts
• Toilet and bathroom extract in offices, hotels and apartments
• Fresh air supply to offices, basements and windowless rooms
• Factory fume and heat extraction
• Car parks, stores and plant rooms

Installing an Extract Fan for a Kitchen

Picture a contractor setting up extract for a restaurant kitchen. First, they mount the fan securely on a solid bracket or base, close to the outside wall. Next, they connect the inlet to the hood duct and the outlet to the duct leading outside. After that, a qualified electrician connects the power supply and checks that the fan spins the right way. Finally, they run the fan and check the airflow at the hood, making sure smoke and steam are drawn away.

Completing the Ventilation System

A fan performs best with tight, well-chosen ductwork. For short connections, use our VENT FLEX foil duct in 4″ to 12″ sizes. Seal every joint with STAR Acry Seal for duct joints so no air leaks. For supply outlets, fit our double-deflection supply grill with damper. For free, natural roof exhaust, add our wind-driven turbine ventilator.

Safety and Handling

• Use a qualified electrician. Power connections must be made safely and to code.
• Isolate before servicing. Switch off and lock out the power before opening the fan.
• Fit guards. Never run the fan with an exposed inlet or outlet.
• Mount it firmly. Bolt it down securely to stop vibration and movement.
• Clean it regularly. Grease and dust on the impeller reduce airflow and can be a fire risk in kitchens.

Frequently Asked Questions

What is the difference between a centrifugal fan and an axial fan?

An axial fan moves air straight through, like a desk fan, and suits open spaces and short runs. A centrifugal fan builds more pressure, so it suits long ducts, filters and hoods.

Can I use it for kitchen extract?

Yes. It’s a common choice for kitchen hoods because it pulls air through long, greasy ducts. Clean the impeller regularly to keep grease from building up.

Why is my extract weak?

Usually, the duct is too long, too narrow, kinked or leaking, or the impeller is dirty. Check the ducting and clean the fan.

How do I choose the right size?

It depends on the airflow you need and the length of the duct run. Call our team with your room size and duct layout, and we’ll advise.

Do you deliver outside Nairobi?

We offer same-day delivery once your order is confirmed, subject to stock availability. Call or email our sales team to confirm stock and arrange delivery to your site.

Order a Centrifugal Fan from Wisdo Merchants

Strong, steady airflow keeps spaces fresh and safe. Our centrifugal fan pushes air through long ducts where ordinary fans give up. Furthermore, you can browse our air conditioning range for ducts, grills and sealants.

Visit us: Dar es Salaam Road, Off Enterprise Road, Industrial Area, Nairobi
Call: +254 795 938305
Email: sales@wisdomerchants.com