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Founded in 1963, MK Plastics is a global leader in the production of corrosion resistant industrial and commercial blowers, fans, and ventilation systems. Patented in several countries, our products are AMCA Certified for Air and Sound Performance.
We offer the broadest and most complete line of quality industrial and commercial corrosion-resistant fans and blowers. Our innovative ventilation technologies are patented in several countries.

The Impact of FEGs on Induced Flow Fans

Artist Name - MKPlastics-B004-014 - The Impact of FEGs on Induced Flow Fans.mp3


The Air Movement and Control Association International (AMCA) developed an energy efficiency classification for fans, which is called AMCA Standard 205. It describes how a fan manufacturer defines fan efficiency grades (more commonly referred to as FEGs). FEGs are a numerical value intended to give the user an indication of the relative efficiency of a product. The higher the number, the more efficient the fan.

AMCA Standard 205 defines FEG based on the peak total efficiency of a manufacturer's fan product design. If a fan is AMCA Certified, that means that the manufacturer's claim of an FEG for that particular fan product has been reviewed and validated by AMCA. AMCA then licenses the manufacturer to certify to the public that the fan meets those FEG specifications.

Fan manufacturers now provide a report card-like number grade that indicates the relative efficiency of a fan product. What's the value in having access to that information? It leads to two outcomes:

1. Designers need to select an efficient fan.

To comply with ASHRAE Standard 90.1 (published in 2013), fans used in buildings must now have a minimum FEG of 67, with a few minor exceptions. The exceptions are PRVs and fans with 5 horsepower or less. All other fans, including induced flow fans, must adhere to the minimum FEG of 67.

2. Fans need to be sized and selected properly.

Compliance with ASHRAE Standard 90.1 also requires fans to be selected within 15 percentage points of its peak total efficiency. To comply with ASHRAE Standard 189, the tighter selection range requires that fans are selected within 10 percentage points of peak efficiency in addition to the minimum FEG of 67.

Remember, ASHRAE requirements do apply to induced flow fans. The total efficiency of an induced flow fan (among other criteria) is an indication of how much discharge or exhaust velocity that the fan can generate for a given amount of power invested in the fan shaft. The higher the discharge or exhaust velocity of an induced flow fan at a given low horsepower, the more efficient that fan may be and the higher the FEG number.

In application, this means that if you have a high velocity exhaust fan with low relative power consumption, that tends to build in a broad safe turndown range, adjusting the fan performance downward with a VFD while still maintaining safe discharge velocities. Those factors greatly influence the product's overall energy savings.

MK Plastics Axijet® induced flow fans all have very high AMCA Certified FEG values. Contact us today so we can assist you with the selection of an energy saving fan that best suits your application.



Shayla: Thank you for joining us today for the MK Plastics Podcast. I'm talking today with Keith Lins. He is the Vice President of US Sales and Marketing at MK Plastics, and Keith, tell me first, what are FEGs and then what is their application and impact on induced flow fans?

Keith: Well, let's start with AMCA, the Air Movement and Control Association International, and specifically, AMCA standard 205. This is the energy efficiency classification for fans publication and it describes how a manufacturer of fans defines fan efficiency grades, which are more commonly referred to as FEGs. So an FEG is an acronym for a fan efficiency grade and it is an index, it's a numeric value intended to give the user an indication of the relative efficiency of that product, so the higher the number, the more efficient the fan.

Shayla: Okay.

Keith: And the standard defines the FEG determination based on the peak total efficiency of a manufacturer's fan product design. FEGs can be determined and they can also be AMCA certified , which means that the manufacturer's claim of an FEG for a fan product has been reviewed and validated by AMCA and then AMCA licenses that manufacturer to certify to the public those FEG values of the fans.

Shayla: Okay.

Keith: So here we are. The fan manufacturer now provides a number that's like a report card number, a grade indicating the relative efficiency of a fan product. So what? That's just more information. Well, the relativity comes in through ASHRAE, and in ASHRAE standard 90.1, the 2013 version, 90.1 now requires that most fans used in buildings for which compliance with 90.1 is required, with a few minor exceptions, must now have a minimum FEG or fan efficiency grade of 67. The exceptions are PRVs and fans 5 horsepower or less. Now, all other fans including induced flow fans must have a minimum FEG of 67. That's the first part of this requirement and the message is, hey, designer, select an efficient fan. The second part of this requires that the fan shall be sized and selected within 15 percentage points of its peak total efficiency and so the message here is not only use an efficient fan, but select it on the right part of the fan curve or select it properly, all right? Now, ASHRAE standard 189 has adopted similar language also requiring a minimum FEG of 67 but 189 tightens up the selection range and requires that the fan be selected within ten percentage points of its peak total efficiency. Now, the ASHRAE requirements do apply to induced flow fans and the mechanical or total efficiency of an induced flow fan among other things is an indication of how much discharge or exhaust velocity that fan can generate for a given amount of power invested in the fan shaft. So, the higher the discharge or exhaust velocity on an induced flow fan, the more efficient—at a given low horsepower—the more efficient that fan may be and the higher FEG number. So what this translates to in application is if you have a high velocity exhaust fan with low relative power consumption, that tends to build in a broad safe turndown range, adjusting the fan performance downward with a VFD while still maintaining safe discharge velocities and that comes into play with energy savings. The MK Plastics Axijet induced flow fans all have very high AMCA certfified FEG values, so contact us for energy saving fan selection assistance.

Shayla: That contact number for MK Plastics is 888-278-9988.

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