Author: longwell

Furnace blower being inspected for loud rumbling noise
By longwell / September 11, 2026 / Fan Engineering Guides

Why Is My Furnace Blower So Loud?

A loud blower usually has one of eight causes, and the sound itself te...

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AC fan in an outdoor condenser unit that keeps stopping
By longwell / September 11, 2026 / Fan Engineering Guides

Why Does My AC Fan Keep Stopping?

A fan that runs then stops is usually protecting itself. Thermal overl...

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Measuring fan vibration at a bearing housing with an analyser
By longwell / September 11, 2026 / Fan Engineering Guides

Fan Vibration: 6 Common Causes

Vibration has a frequency signature, and that signature names the faul...

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Technician checking a blower that runs but produces no airflow
By longwell / September 11, 2026 / Fan Engineering Guides

Blower Runs But No Airflow — What’s Wrong?

A motor that spins while nothing comes out of the vents has a short li...

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EC-Motor-vs-DC-Motor-vs-AC-Motor--Effic
By longwell / September 11, 2026 / Technical Articles

EC Motor vs DC Motor vs AC Motor: Efficiency & Cost Comparison

Electric motor-driven systems account for approximately 65% of industr...

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Curve showing where centrifugal fans surge, left of the pressure peak
By longwell / September 10, 2026 / Fan Engineering Guides

Why Do Centrifugal Fans Surge? (Stall Explained)

Surge is what happens when a fan is pushed too far left on its curve. ...

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Checking whether a fan is spinning in the wrong direction against the housing arrow
By longwell / September 10, 2026 / Fan Engineering Guides

Fan Spinning Wrong Direction? How to Check

A reversed fan still turns, still sounds normal and still draws power,...

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Thermal camera image of an overheating fan motor under load
By longwell / September 10, 2026 / Fan Engineering Guides

Overheating Fan Motor: Causes & Fixes

Heat is what kills motors, and almost every overheating case traces ba...

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Testing the signal on an EC fan not responding to its controller
By longwell / September 10, 2026 / Fan Engineering Guides

Why Is My EC Fan Not Responding to Control Signal?

A fan that runs at one speed regardless of the signal usually has a wi...

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Blower wheel with uneven dirt build-up causing imbalance
By longwell / September 10, 2026 / Fan Engineering Guides

Blower Wheel Out of Balance: Symptoms & Fix

An unbalanced wheel announces itself through vibration at exactly one ...

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