Plate Axial Fans

Frequently asked questions

What is a plate axial fan?

A plate axial fan is an axial-flow fan mounted on a square or circular steel plate, designed to be fitted directly through an external wall or bulkhead. Air moves parallel to the fan's axis, in a straight line through the impeller. Plate axial fans shift large volumes of air at low static pressure, which makes them ideal for direct through-wall extract or supply where ductwork runs are short or absent. They are also called axial plate fans, plate mounted axial fans or plate mounted axial flow fans, all referring to the same product type.

Plate axial fan or cased axial fan?

A plate axial fan is mounted on a flat plate and fixed through a wall or bulkhead, with no surrounding duct housing. A cased axial fan sits inside a cylindrical duct case with flanged connections and is installed inline on ductwork. Plate axials handle short direct runs and high airflow at low pressure; cased axials handle longer ducted systems with multiple grilles and higher pressure drops. For warehouse through-wall extract, plate axial is the right choice. For multi-zone ducted schemes, specify cased axial.

What sizes of plate axial fan are available?

eFans stocks plate axial fans from 200mm right up to 900mm. Common sizes: 200mm and 250mm for small plant rooms, cellars and light commercial; 300mm, 315mm and 350mm for workshops and small commercial units; 400mm and 450mm for typical warehouses and factories; 500mm, 560mm and 630mm for larger industrial buildings; 710mm, 800mm and 900mm for high-airflow applications like large distribution centres and manufacturing. Bigger fans move more air at lower rotational speed, so they are quieter and more efficient for the same duty than smaller fans running flat out.

Single-phase, three-phase or EC plate axial fans?

Single-phase (230V) AC fans suit smaller sizes (up to around 400mm) or any building without a three-phase supply. Three-phase (400V) AC fans are standard on larger plate axials (450mm and up) in commercial and industrial buildings, being more efficient and cheaper to run at scale. EC motors (electronically commutated) are the modern alternative: 30 to 50% more efficient than AC, soft-starting, infinitely variable via a 0-10V signal, and specified on new commercial projects where Part L compliance or BMS integration matters. Systemair's AW EC range is the widest EC plate axial line we stock.

How do I size a plate axial fan?

Calculate the air changes per hour (ACH) the application needs: typically 4 to 6 ACH for general ventilation, 8 to 10 ACH for workshops and busy production areas, 15 to 30 ACH for kitchens and heat-load zones. Multiply building volume in m³ by ACH to get the m³/h airflow requirement. Match that against the fan curve, allowing for any static pressure loss through external louvres or cowls. As a rule of thumb, one 400mm plate axial covers around 200 to 400m² of floor at typical commercial ceiling heights; one 600mm covers 500 to 800m². Oversize slightly and run via speed controller, which is quieter, longer-lasting and more efficient.

Which brand: S&P, Systemair, Hydor, Elta or Vent-Axia?

All five are reputable. S&P's HCBB, HCBT and HXBR Silent range is the widest general-purpose line and usually the best value at mid sizes (250 to 630mm). Systemair AW Sileo is the quietest and the only range with a full EC motor option, specified on new commercial projects. Hydor's HPA Compact range is the most compact for tight installations and offers strong value at small-to-mid sizes. Elta's SCP Compact and SPA Raptor ranges are popular with M&E contractors, the Raptor in particular being a robust industrial plate axial. Vent-Axia is typically specified on refurb projects where the rest of the ventilation scheme is Vent-Axia. If you are not sure, we will match a fan to your duty and budget.

How to choose the right plate axial fan

The correct plate axial fan should be selected based on airflow requirement, wall opening size, operating environment, and resistance within the system. Start by calculating the required extract or supply volume in m³/h, then match this to the fan's duty point and available aperture size.

You should also consider voltage, noise level, speed control compatibility, and whether the fan will operate continuously or intermittently. For commercial and industrial spaces, choosing the correct IP rating and motor duty class is equally important to ensure long-term reliability.

What applications are plate axial fans used for?

Through-wall extract and supply in almost any commercial or industrial building: warehouses, factories, distribution centres, workshops, MOT bays and vehicle workshops, commercial kitchens (paired with a grease filter), car parks (fitted to plenums or directly through walls), agricultural buildings and livestock sheds, plant rooms, substations, transformer enclosures, swimming pool halls, laundries, and any space that needs high-volume direct ventilation without the cost and complexity of ductwork. Not usually the right fan for domestic or small-scale MVHR, where an inline or MVHR unit should be specified instead.

How are plate axial fans installed?

Cut an opening in the external wall to match the fan plate dimensions (published on each product's data sheet). Fix the fan plate to the internal face of the wall via the mounting holes on the plate, typically M8 fixings into appropriate anchors. Seal around the plate with silicone or gasket strip for a weather and acoustic seal. Fit an external weather louvre or cowl on the outside face to shed rain and stop pests. Wire the fan through an isolator and, where specified, a speed controller. Allow sufficient internal clearance in front of and behind the fan for airflow and service access. For multi-fan installs, space units evenly across the wall to balance airflow across the building.

Are plate axial fans speed controllable?

Yes, every plate axial fan eFans stocks is speed controllable. AC motors (both single and three-phase) run with a 5-step speed controller or electronic variable speed controller sized to the fan's FLC. EC motors accept a 0-10V signal from a BMS, thermostat, timer or manual potentiometer and run infinitely variable. Running below full speed reduces noise, cuts energy use significantly, and extends motor life. For multi-fan warehouse installs we recommend one controller per zone or per group of three-to-five fans rather than one controller for the whole building.

Do you do trade pricing on plate axial fans?

Yes. eFans supplies M&E contractors, ventilation installers, facilities teams and maintenance contractors across the UK. Trade accounts with net payment terms are available to regular buyers. Send us your schedule, drawing or brief and we will size the scheme, quote matched fans, controls and louvres, and arrange next-day or scheduled site delivery. Contact hello@efans.co.uk or call 0161 399 3825.