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AirFlow Technology

In-Line Duct Fans

In-Line Duct Fans
What is Free Air?

The truth about "Free Air" and "Boosted Air" Ratings! As an online consumer it is important for you to understand what it is you are buying before you purchase because you don't have the ability to actually look at the product and see it function. There are some manufacturers out there who would like you to believe you are buying something you are not. As an example you may think you are buying a 500 CFM rated fan but in reality you are getting a 210. Be sure you know the "Free Air" ratings of your duct fan before you purchase. We explain a little more in detail below. "Free Air" is a rating given to a fan that is not installed in a duct line. There is no restriction to airflow or static pressure (This is the rating you would get if you simply have the fan plugged in and sitting on a table in front of you). "Boosted Air" is a rating given to a fan as a maximum number of CFM's the duct fan will push before it becomes a restriction itself. It does not mean you will even come close to this "Boosted" number and it is based on a certain number of CFM's pushing on the back end of the duct fan from your main blower in order to help the duct fan generate more rpms thus more CFM's. Chances are if you are having airflow problems to begin with you are not going to have alot of CFM's pushing on the back end of your duct fan let alone enough to even get you close to the "Boosted Air" rating you thought you were going to get. "Free air" is really the only fair way to rate these duct fans due to the amount of variables within each setup like duct length, 90 or 45 degree bends, how many CFM's are pushing on the back end from your main blower and where you plan to install your duct fan. We hope this information helps in your purchasing decisions. Please contact us for further details if needed.

 
What is a Centrifugal Inline Duct Fan?
These fans are the best fans on the market. Able to withstand massive amounts of static pressure and
resistance to airflow these fans are the cure-all to your problem room. The centrifugal design keeps the motor
out of the air stream while pushing the air out at a fast pace. Quality product with a
5 YEAR WARRANTY!!!

 
Why use Aero-Flo Centrifugal Duct Fans?
5 Year Manufacturer Warranty!!!
We show you the curve ratings! How many other sites actually show you the performance curves? Just because it has a High CFM rating doesn't mean its going to perform well under restrictive conditions. Be sure you know the curves before you buy!
Massive power to push past restriction.
Boost and maximize airflow to hard to HEAT or COOL rooms!
Exhaust air from your Bathroom, Kitchen or Garage!
Great for use as a Greenhouse Fan or Hydroponic Fan!
Boost your return air to gravity flow furnace!
Save energy costs by maximizing your heating and cooling system!
 
What are CFM's?
CFM stands for Cubic Feet Per Minute and in this application it is defined as a rate of airflow. Most CFM ratings are measured in a controlled environment persuant to specific industry standards. Higher CFM ratings do not always mean a stronger fan it simply means there is more space for the air to flow through. If you see a 425 CFM 6" Fan and compare it to a 1100 CFM 12" you think automatically the 12" is much more powerful unit when in fact it moves at about the same RPM and reacts to restriction in much the same way as a 6 inch unit does. The fact the 12" unit has 12 inches of free air space is the main reason it has a much higher CFM rating.