Mixed Flow Fans
Greenheck’s mixed flow fans are the quietest tubular inline fans in the industry! Mixed flow inline fans can be used for supply, exhaust, or return air installations. Our patented design excels in commercial applications where low sound is critical. In addition, Greenheck’s mixed flow fans are more efficient than comparably sized tubular centrifugal and vane axial fans, thus reducing the required motor horsepower and lowering operating costs.
Mixed flow fans are recommended for any ventilation application that requires low sound and high efficiency, such as office buildings, parking garages, concert halls, libraries, and educational facilities.

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What's New
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Application Information
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Project Profiles
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General Information
Overview
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Model QEI
The QEI has a belt drive construction with motor out of the airstream. Air Handling Quality bearings are selected with a minimum life in excess of L(10) 80,000 hours at the maximum operating speed. Performance capacities from 500 to 115,000 cfm (850 - 195,386 m3/hr) and pressures up to 8.5 in. wg. (2120 Pa).
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Model QEI-L
The QEI-L has belt drive construction with motor out of the airstream. Air Handling Quality bearings are selected with a minimum life in excess of L(10) 80,000 hours at the maximum operating speed (horizontal mount). Performance capacities range from 700 – 40,000 cfm (1,190 – 67,960 m3/hr) and pressures up to 5 in. wg. (1245 Pa)
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Model QEID
The QEIDs direct drive construction eliminates belts, pulleys, and shaft bearing maintenance. It’s design is more compact for space critical application. And, the QEIDs partial wheel widths allow for wide performance capacities ranging from 800 to 83,000 cfm (1,700 - 141,000 m3/hr) and pressures up to 10.5 in. wg. (2370 Pa).
Catalogs
- Coatings for Extreme Applications
- Dampers for Centrifugal Fans
- Marine Products - Dampers, Louvers and Fans
- Mixed Flow Fans from Models QEI-L, QEI, and QEID
- Sure-Aire Flow Monitoring System
Performance Supplements
Instruction Manuals
Drawings
| Configured Model Selection CAPS required to Create |
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QEI | In CAPS | Transmit | In CAPS | Download | Download |
QEI-Horizontal Discharge
QEI-Vertical Discharge |
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QEID | In CAPS | Transmit | In CAPS | Download | Download | |||
Other Info
Greenheck's Total Fan Package
Greenheck offers a complete fan package including your choice of- Motors and Drives
- Protective Coatings
- Safety Guards and Motor Covers
Sound Vault Specification
Panels of the outer housing shall be constructed out of galvanized steel. Minimum galvanized material gage thickness to be 16 gauge. Enclosure walls shall be lined with sound dampening fiberglass insulation having a thickness of two inches (51 mm) and density of 3 lbs. / ft2. Exterior collars shall provide a connection point for system ductwork. Enclosure shall have quick opening and fully removable gasketed access panel(s) to provide access to all internal components.
To limit breakout noise, inlet and outlet of fan shall be connected to the inside of the enclosure using a slip-fit flexible duct connection. In addition, Sound Vault shall be supplied from factory with internally mounted, one-inch (25 mm) deflection free standing spring isolators.
Grease filled lubrication lines shall be extended to the exterior of the Sound Vault enclosure. Nylon lines will provide lubrication to fan bearings without removing fan from enclosure. Wiring for fan power supply shall be extended to the exterior of the Sound Vault enclosure and electrical connections shall be terminated at an electrical box.
Sound Vault enclosure shall be supplied with two formed steel mounting rails. Rails shall be securely fastened to enclosure and have pre-punched holes in both ends to provide for either ceiling hung or floor mounting configurations.
Radiated sound power attenuation ratings shall be based on factory tests using sound intensity measurement techniques on of both the fan and sound enclosure in combination. Radiated sound power reductions from total sound power shall be available for each of eight octave bands with center frequencies (hz) of 63, 125, 250, 500, 1000, 2000, 4000, and 8000.
Sound Vault enclosure shall be fully assembled with fan at the factory and shipped as a complete assembly up through QEI fan size 27. Temporary restraining brackets are mounted internal to the Sound Vault enclosure to limit movement of fan during transit.
The advantages of buying a complete fan package from Greenheck include proper selection, design, testing, and manufacturing.


