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    Centrifugal Downblast Exhaust Fan, Product # GB-300-20140X3QD-DR1

    Centrifugal Downblast Exhaust Fan, Product # GB-300-20140X3QD-DR1

    • 40 x 40 inch base with prepunched mounting holes for easy attachment to roof curb
    • Variable pitch adjustable motor pulley to optimize fan performance
    • 32.5 x 32.5 inch recommended roof opening
    • Shipping Type:
      Freight
    $2,474.15
    In stock 
    Free shipping
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    • 40 x 40 inch base with prepunched mounting holes for easy attachment to roof curb
    • Variable pitch adjustable motor pulley to optimize fan performance
    • 32.5 x 32.5 inch recommended roof opening
    • Shipping Type:
      Freight

    Model GB, belt drive centrifugal roof exhaust fans are designed to meet the general clean air exhaust requirements for industrial and commercial buildings. Units feature a fully rolled windband bead for increased stability and easy transport. Fresh outside air is drawn in under the motor cover to maximize motor life. Ideal for new installations or for retrofit, replacement applications. Curb adapters and reducers available to eliminate the need to field fabricate transitions when there is an existing roof curb.

    • Centrifugal wheel provides high-efficiency and minimal sound
    • True vibration isolation supports the motor and wheel for long life and quiet operation
    • One-piece aluminum curb cap provides a weather-tight fit
    • Galvanized birdscreen protects the fan discharge from birds and small objects
    • Fully rolled windband bead for increased stability and easy transport
    • Positive motor cooling with fresh air results in maximm motor life
    • Permanent embossed aluminum nameplate for exact model and serial number identification
    • Suitable for High Wind applications
    • Motor, belt and pulleys shipped loose for field assembly
    California Residents - Prop 65 Warning
    Specifications
    Base/Panel Length X Width
    40 x 40 in
    Curb Cap Size
    40 in
    Impeller Diameter
    30 3/4 in
    Roof Opening Width x Roof Opening Length
    32 1/2 x 32 1/2 in
    Base Height
    1 3/4 in
    Base Top to Shroud Top
    36 in
    Damper Width x Damper Height
    30 x 30 in
    Bearing Size
    1 in
    Height
    36 in
    Weight
    150 lbs
    Overall Diameter
    50 in
    Application
    Exhaust General and Clean Air
    High Wind
    Housing Material
    Spun Aluminum
    Drive Type
    Belt Drive
    Impeller Type
    Centrifugal Wheel
    Impeller Material
    Aluminum
    Includes
    Unassembled drive package
    Certifications
    AMCA Sound & Air
    High Wind and Hurricane
    Seismic
    UL/cUL 705
    Drive Package Description
    Motor and drives shipped loose
    Required Accessory
    Roof curb for new installations
    Motor Insulation
    F
    Motor Phase
    3
    Service Factor
    1.15
    Voltage
    208
    230
    460
    HP
    2
    Hertz
    60
    Motor Enclosure
    Open Drip Proof
    RPM
    1800
    Thermal Protection
    No
    Nominal Efficiency
    86.5
    Shipping Type
    Freight
    Warranty Length
    1 Year
    Performance
    CFM Range
    4663-8747
    FRPM Range
    490-540
    Ps (in. wg) 0 0.125 0.25 0.375 0.5 0.625 0.75
    2 1.13 540 490 CFM 8747 8320 7824 7294 6684 5933 4663
    Sones 14 13.5 12.8 12.2 11.4 10.3 10
    Bhp 1.06 1.09 1.12 1.13 1.13 1.1 1
    2
    1.13
    540
    490
    Ps (in. wg) CFM Sones Bhp
    0 8747 14 1.06
    0.125 8320 13.5 1.09
    0.25 7824 12.8 1.12
    0.375 7294 12.2 1.13
    0.5 6684 11.4 1.13
    0.625 5933 10.3 1.1
    0.75 4663 10 1
    • Greenheck Fan Corporation certifies that the model shown herein is licensed to bear the AMCA Seal. The ratings shown are based on tests and procedures performed in accordance with AMCA Publication 211 and AMCA Publication 311 and comply with the requirements of the AMCA Certified Ratings Program.
    • Performance certified is for installation type A: Free inlet, Free outlet.
    • Power rating (BHP/kW) includes transmission losses.
    • Performance ratings include the effects of birdscreen.
    • The sound ratings shown are loudness values in fan sones at 5 ft. (1.5 m) in a hemispherical free field calculated per AMCA Standard 301. Values shown are for installation type A: free inlet hemispherical sone levels.
    Videos

    Common methods for tensioning a rooftop exhaust fan belt

    Centering a wheel on a spun aluminum rooftop exhaust fan

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