4 inch inline exhaust fans review

Introduction to 4 inch inline exhaust fan

A ventilation of your grow space is essential for your plants well-being and a must for indoor gardens of any size.


A 4 inch inline extractor fan with proper ducting and accessories:

  • Provides fresh air and brings in needed carbon dioxide
  • Helps regulating climatic conditions (heat and humidity)
  • Controls dust and mold
  • Reduces odors


Without it your plants will have a hard time expressing their full potential and you might be confronted to excessive heat or humidity, resulting in poor growth or fungal invasion.

That’s why you want to make sure the air circulation around your crop is adequate by choosing the proper equipment to keep your plants cool and happy all the time.


Is a 4 inch inline fan quiet?

Well, not exactly. Most of the fans can be noisy and create an unbearable nuisance in the quiet of your relaxing home. Various items and improved fans can be purchased in order to regulate the emitted sound.


4 Inch Inline Exhaust Fan Review 2018

Soler & Palau TD-100XS In-line Exhaust Fan

price $$$

rating 4 stars

  • Class I electrical insulation IP 44 protection thermal overload protection Class B motor insulation sealed for life
  • Safety tested by Underwriters Laboratories, Inc. and are UL and cUL Listed. ETL Listed
  • 4’’ Inline mixed flow duct fan-H: 203 cfm, L: 108 cfm


This is a top shelf fan. Designed to ensure the most quiet use, it’s been reported to do the job very smoothly. It’s light-weighted, has a high CFM rating and its motor insulation prevents vibrations, which is a great feature if you plan on hanging it in a grow tent, as most of the fans can cause heavy structural shaking.

Definitely worth the price, it’s a must for anyone seeking discretion.



Active Air 4 inch In-Line Fan 165 CFM

price $$

rating 4,5 stars

  • Durable ceramic-coated housing
  • UL-recognized components
  • Includes mounting brackets and 8 foot pre-wired 120V cord


Even if it’s not good as the previous one, this is a great little fan! Really long lasting and sturdy, it’s been designed to work 24/7 and comes at a very decent price. However, it has been reported to produce a strong noise and is thus recommended for growers on a lower budget or those planning further investments in soundproofing accessories.


Inline fan speed controller


It’s a simple trick known to most growers:

choose a fan with a CFM rating exceeding your needs and lower its speed. The noise will be reduced accordingly!



Active Air ACSC Duct Fan Speed Adjuster

price $

rating 4 stars

  • Correctly and precisely adjust the speed of centrifugal fans
  • Rated for 15 amps
  • Internal, electronic auto-resetting circuit breaker


This item has multiple advantages: it will help you adjust the air flow to meet your grow-room requirements  while providing a significant noise level reduction at the same time!


If you wish more information or hesitate between a 4 inch, an 8 inch inline fan or a 6 inch exhaust fan, take a look at our dedicated section! We have the best and most up-to-date reviews about any piece of growing equipment you may need!


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