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Whirlwind Powered Extract Ventilator

The Whirlwind is a low profile, upward discharge, roof or wall mounted powered extract ventilator designed to deal with localised air quality and overheating problems as well as to provide general comfort control. It is suited to most industrial and commercial buildings.

General information
Specification data - Roof-mounted fans

Product Reference

Whirlwind Powered Ventilator 500-W4/05

500 mm nominal fan size.

Whirlwind Powered Ventilator 630-W4/06

630 mm nominal fan size.

Whirlwind Powered Ventilator 800-W4/08

800 mm nominal fan size.





Motor option

Single phase

For 500 mm and 630 mm units.

Three phase

For 500 mm, 630 mm and 800 mm units.




Mill finish

Polyester powder coating


Manufacturer's standard via mill finish

RAL colour

Standard product features

Whirlwind is manufactured to the ISO 9000 quality standard.


A non-return shutter opens when the fan is in use and locks closed when the fan stops running.

Bases and installation:

Whirlwind can be orientated at any angle from the horizontal to the vertical. Its wide range of base types and the fact that it is lightweight means that it can be installed into nearly any type of roof or wall structure. All versions except the 800 mm unit can be installed directly into glazing.


Whirlwind produces airflows of between 1.5 m³/s and 4.8 m³/s. Its noise output ranges from 49 to 67 dB(A) at 3 m.

Product Options

Nominal fan sizes:

  • 500 mm.
  • 630 mm.
  • 800 mm.

Motor option:

  • Single phase for 500 mm and 630 mm units.
  • Three phase for 500 mm, 630 mm and 800 mm units.


  • Mill finish.
  • Polyester powder coating to a RAL colour.

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