Fan Performance Curves

A fan curve plots pressure against airflow at fixed speed; where it crosses the system resistance curve is the real operating point. Learn to read total vs static pressure curves, spot stall regions, apply fan laws for speed changes and understand why catalogue and field numbers differ.

Regenerative blower with side channel housing beside a centrifugal blower
By longwell / August 22, 2026 / Fan Engineering Guides

Centrifugal vs Regenerative (Side Channel) Blower

A regenerative blower recirculates air through the impeller many times...

Read More »
Ducted and ductless ventilation arrangements compared in a kitchen
By longwell / August 22, 2026 / Fan Engineering Guides

Ducted vs Ductless Ventilation

Ductless systems filter and return air rather than removing it. That w...

Read More »
Single inlet and double inlet centrifugal fan wheels compared
By longwell / August 21, 2026 / Fan Engineering Guides

Single Inlet vs Double Inlet Centrifugal Fans: What are different?

A double inlet wheel takes air from both sides, roughly doubling airfl...

Read More »
How-to-Replace-Fan-Motor-Beari
By longwell / August 18, 2026 / Fan Engineering Guides

How to Replace Fan Motor Bearings?

Bearing replacement is not the first answer to every noisy fan motor. ...

Read More »
LONGWELL centrifugal fan
By longwell / August 11, 2026 / News

Centrifugal HVAC Fans: Complete Ordering Guide

Centrifugal fans are widely used in AHUs, ventilation equipment, and H...

Read More »
air circulator vs industrial fan
By longwell / August 7, 2026 / News

Air Movement Solutions: From Air Circulators to Industrial Fans

Air movement is essential in an HVAC system to circulate air and regul...

Read More »
duct fan vs exhaust fan
By longwell / August 5, 2026 / News

Duct Fan vs Exhaust Fan: What are the Differences?

Effective ventilation is essential for maintain indoor air quality, co...

Read More »
Tube Axial Fan vs Tube Axial Fan
By longwell / July 28, 2026 / News

Vane Axial Fan vs Tube Axial Fan: Which Handles Higher Pressure?

Axial fans are widely used in ventilation systems to convey large amou...

Read More »
LONGWELL factory
By longwell / July 22, 2026 / News

Centrifugal Fan OEM: What to Ask Your Manufacturer?

When you are deciding which centrifugal fan to use in the systems, you...

Read More »
LONGWELL duct fan
By longwell / July 21, 2026 / News

How to Install a Duct Fan: Step-by-Step Guide

The ducts in HVAC systems are usually long. When the airflow goes thro...

Read More »