At Airtècnics, as specialists in ventilation solutions and air curtains, we address in this guide the types of fans, their technical characteristics and their real-world applications, with a practical approach oriented towards engineering and technical specification.

What is a fan and how does it work?

A fan is a set of motor and rotating blades that transfers mechanical energy to the air through an impeller, generating a controlled flow. This flow is used for ventilation, extraction, transport or cooling.

Key technical parameters

• Flow rate (Q): volume of air displaced (m³/h or m³/s)
• Static pressure (Pa): capacity to overcome resistance
• Absorbed power (W): energy consumption
• Efficiency (%): ratio between useful and consumed energy

According to the IDAE (Institute for Energy Diversification and Saving), the optimal operating point should be close to the maximum efficiency of the fan to minimise consumption and wear.¹

Fan classification

1. According to airflow path

Axial fans

Air flows parallel to the axis of rotation. They are the most widely used in general ventilation. See Airtècnics axial fans

• High flow rates: up to >200.000 m³/h
• Low pressure: typically < 500 Pa
• High efficiency in open applications

Applications:

• Industrial warehouse ventilation
• Equipment cooling
• HVAC systems

Centrifugal fans

Air enters axially and is expelled radially, generating higher pressure.

• Pressure: up to >10.000 Pa
• Greater capacity for complex ducts
• Better performance against pressure drops

Applications:

• Smoke extraction
• Industrial filtration
• Chemical processes

Tangential fans

They generate a uniform flow along their entire length. They are used in some Airtècnics air curtain models, such as the Optima, the Aris or the TOP design air curtain.

Applications:

• Air curtains
• Compact HVAC units

Mixed-flow fans

An intermediate solution between axial and centrifugal.

• Medium pressure
• Compact design
• Installation versatility

2. According to generated pressure

3. According to impeller design

• Forward-curved blades: high flow rate, lower efficiency
• Backward-curved blades: higher energy efficiency
• Radial blades: maximum robustness (dust, particles)

The choice of impeller directly affects the energy consumption and noise level of the system.

Types of fans according to their application

Industrial fans

Designed for demanding conditions:

• High temperatures
• Corrosive environments
• Suspended particles

Air extractors

Essential for indoor air renewal.

• Bathrooms
• Industrial kitchens
• Car parks

Tunnel fans and jet fans

Used for smoke control and longitudinal ventilation.

Fans in air curtains

Key to energy efficiency at commercial and industrial access points.

More information: What is an air curtain?

Technical criteria for selecting a fan

• Required flow rate
• System pressure drops
• Noise level (dB)
• Energy efficiency (ErP)
• Environmental conditions
• Maintenance and service life

A poor selection can increase energy consumption by up to 30%, according to HVAC sector studies.

Innovation in fans

• EC motors (Electronically Commutated)
• Intelligent speed control
• Advanced aerodynamic designs
• Noise reduction

These technologies make it possible to improve efficiency and reduce operating costs of ventilation units.

Conclusion

Choosing the right fan depends on the balance between flow rate, pressure and application. In industrial and commercial environments, this decision directly impacts energy efficiency and the overall performance of the system.

At Airtècnics, we develop advanced ventilation solutions tailored to each project, combining innovation, efficiency and reliability.

Frequently asked questions (FAQ)

Which type of fan is best?

It depends on the application. But, in general, axial fans are used for high flow rates at low pressure and centrifugal fans for high pressure and controlled flow rates.

How do you calculate the right fan?

Flow rate, pressure drops and environmental conditions must be analysed. 

Which fan is most efficient?

Backward-curved blade fans with EC motors are the ones that offer the highest efficiency. Their PlugFan variant, manufactured in Germany by Rosenberg Ventilatoren, offers maximum efficiency.