32
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.
Damper Size = 18 x 18 (457 x 457)
Roof Opening = 20 x 20 (521 x 521)
Shroud Thickness = 0.064 (1.6)
Motor Cover Thickness = 0.040 (1.0)
Curb Cap Thickness = 0.064 (1.6)
^Approximate Unit Weight = 166 lbs. (75 kg)
All dimensions in inches (millimeters). *May be greater depending on
motor. ^Weight shown is largest cataloged Open Drip-Proof motor.
Roof Downblast - Exhaust
Belt Drive
GB-220HP
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)
3
Volume (m /hr)
RPM (Belt)
HP
Density 0.075 lb/ft
3
Density 1.2 kg/m
3
Motor
HP
Fan
RPM
Static Pressure in Inches wg
0.5 0.75 1 1.25 1.5 2 2.5 2.75 3 3.25
200HP
1/2
740
CFM
1961
BHP
0.30
Sones
8.7
895
CFM
2809 2331 1424
BHP
0.52 0.53 0.45
Sones
11.4 10.9 10.3
3/4
958
CFM
3116 2715 2153
BHP
0.63 0.65 0.63
Sones
12.8 12.1 11.6
1020
CFM
3409 3050 2602 1857
BHP
0.75 0.77 0.78 0.71
Sones
14.1 13.6 13.1 12.6
1 1125
CFM
3885 3584 3243 2804 2136
BHP
0.99 1.02 1.04 1.04 0.97
Sones
16.9 16.4 15.5 15.3 15.2
1
1
⁄2
1205
CFM
4229 3967 3663 3314 2884
BHP
1.19 1.24 1.27 1.29 1.27
Sones
18.8 17.9 17.2 16.5 16.4
1285
CFM
4569 4343 4070 3770 3416 2278
BHP
1.43 1.49 1.52 1.55 1.57 1.40
Sones
21 20 19.1 18.1 17.8 18.9
2
1350
CFM
4843 4638 4384 4109 3811 2996
BHP
1.65 1.71 1.75 1.78 1.81 1.76
Sones
23 22 21 19.8 19.3 19.1
1415
CFM
5114 4919 4692 4442 4169 3492 2250
BHP
1.88 1.95 2.00 2.04 2.07 2.07 1.78
Sones
24 24 23 22 21 19.7 23
3
1520
CFM
5550 5368 5182 4952 4713 4166 3458 2850 2046
BHP
2.31 2.38 2.45 2.50 2.53 2.58 2.53 2.38 2.06
Sones
27 27 27 26 24 23 22 22 22
1625
CFM
5982 5812 5642 5448 5233 4767 4196 3859 3377 2725
BHP
2.80 2.88 2.95 3.02 3.06 3.13 3.16 3.12 3.01 2.76
Sones
32 31 31 29 28 27 25 24 23 22
MAXIMUM BHP AT A GIVEN RPM = (RPM/1106)
3
MAXIMUM RPM = 1625
TIP SPEED (ft/min) = RPM x 5.596
MAXIMUM MOTOR FRAME SIZE = 184T
1
3
⁄4 (44)
5
1
⁄2 (140)
*28
(711)
30
(762)
35
1
⁄2
(902)
