Filter
Top Products
35
Roof Downblast - Exhaust
Belt Drive
GB-240
Performance certified is for installation type A: Free inlet, Free outlet. Power rating (BHP) does not include transmission losses. Performance ratings include the effects
of a birdscreen. The sound ratings shown are loudness values in hemispherical 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.
Performance certified is for installation type A: Free inlet, Free outlet. Power rating (BHP) does not include transmission losses. Performance ratings include the effects
of a birdscreen. The sound ratings shown are loudness values in hemispherical 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.
1
3
⁄4 (44)
Damper Size = 24 x 24 (610 x 610)
Roof Opening = 26 x 26 (673 x 673)
Shroud Thickness = 0.064 (1.6)
Motor Cover Thickness = 0.040 (1.0)
Curb Cap Thickness = 0.064 (1.6)
^Approximate Unit Weight = 165 lbs. (75 kg)
All dimensions in inches (millimeters). *May be greater depending on
motor. ^Weight shown is largest cataloged Open Drip-Proof motor.
D
O
N
O
T
S
E
L
E
C
T
T
O
T
H
E
L
E
F
T
O
F
T
H
I
S
S
Y
S
T
E
M
C
U
R
V
E
Static Pressure (in. wg)
Static Pressure (Pa)
Volume (cfm x 1000)
3
Volume (m /hr x 1000)
RPM (Belt)
HP
Density 0.075 lb/ft
3
Density 1.2 kg/m
3
Motor
HP
Fan
RPM
Static Pressure in Inches wg
0 0.125 0.25 0.375 0.5 0.625 0.75 1 1.25 1.5
240
1/4
425
CFM
3902 3422 2691
BHP
0.19 0.21 0.20
Sones
5.9 5.9 4.7
460
CFM
4223 3785 3188 2036
BHP
0.24 0.26 0.27 0.22
Sones
6.7 6.6 5.7 4.2
1/3 505
CFM
4637 4242 3761 3060
BHP
0.32 0.35 0.35 0.34
Sones
7.8 7.5 6.9 6.1
1/2 585
CFM
5371 5031 4666 4195 3562 2112
BHP
0.50 0.53 0.54 0.55 0.53 0.41
Sones
10.3 9.7 9.1 8.8 8.2 7.2
3/4
623
CFM
5720 5400 5069 4660 4131 3428
BHP
0.60 0.64 0.65 0.66 0.65 0.61
Sones
11.7 11.0 10.4 10.0 9.6 9.1
660
CFM
6060 5757 5449 5094 4636 4073 3217
BHP
0.71 0.75 0.78 0.79 0.78 0.76 0.69
Sones
13.1 12.4 11.8 11.3 11.0 10.6 10.4
1 730
CFM
6702 6428 6158 5861 5507 5077 4568
BHP
0.96 1.01 1.05 1.05 1.06 1.06 1.03
Sones
15.8 15.0 14.3 13.8 13.4 13.1 12.9
1
1
⁄2
778
CFM
7143 6886 6632 6363 6058 5700 5266 4145
BHP
1.16 1.21 1.26 1.27 1.28 1.29 1.28 1.18
Sones
17.7 16.6 15.9 15.4 15.0 14.7 14.4 13.2
825
CFM
7575 7332 7092 6844 6574 6261 5901 5002
BHP
1.39 1.44 1.49 1.51 1.52 1.54 1.53 1.48
Sones
19.7 18.6 17.7 17.2 16.8 16.4 16.2 14.8
2
870
CFM
7988 7757 7529 7300 7055 6775 6457 5680 7757
BHP
1.63 1.68 1.73 1.77 1.78 1.80 1.80 1.77 1.68
Sones
22 21 19.6 19.1 18.7 18.3 17.9 16.9 21
910
CFM
8355 8135 7916 7700 7467 7215 6933 6240 5388 3707
BHP
1.86 1.92 1.97 2.02 2.03 2.05 2.06 2.05 1.97 1.66
Sones
24 23 21 21 21 20 19.6 19.2 16.7 13.6
MAXIMUM BHP AT A GIVEN RPM = (RPM/715)
3
MAXIMUM RPM = 910
TIP SPEED (ft/min) = RPM x 6.414
MAXIMUM MOTOR FRAME SIZE = 184T
42
3
⁄4
(1086)
*31
1
⁄2
(800)
5
3
⁄4 (146)
34
(864)