Exhaust Fan Sizing Checklist
Measure these before you ask for a quotation
- Space length, width, and height, and the volume that follows from them
- Heat sources and their location in the space
- Existing openings: size, position, and whether they can be used as inlets
- Pad or filter in the air path, and its size
- Duct length and bends, if the fan will be ducted
- Voltage, frequency, and phases available
- Noise limits that apply to the site or to neighbouring buildings
- Access for maintenance: can the fan, belt, and motor be reached safely?
Questions to ask the supplier
- Is the airflow figure free-air or measured against a stated resistance?
- What is the noise figure measured at, and under what conditions?
- What spare parts are supplied, and what is their lead time?
- What warranty covers the motor, the blade, and the housing, separately?
No sizing formula is published on this page, deliberately. A formula without the resistance of your pads, ducts, and openings produces a precise-looking number that is wrong for your space. The checklist above is what a supplier needs to size the fan correctly, and a supplier who sizes from a single room volume alone should be asked what resistance they assumed.
Before ordering, confirm: the exact model and voltage for your site, the airflow and size you need, MOQ, lead time, and warranty. This page lists only what the source material verifies; anything not listed here is a question to ask, not a specification to assume.
Request a ventilation and cooling layout
Send your space size, heat source, and voltage, and ask for a layout using the equipment families on this page. Before payment, confirm MOQ, lead time, voltage, and warranty for your order.