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Static Pressure (in. wg)
Static Pressure (Pa)
Volume (cfm)
3
Volume (m /hr )
RPM (Belt)
RPM (Direct)
RPM (Vari-Green)
HP
Density 0.075 lb/ft
3
Density 1.2 kg/m
3
23
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 = 12 x 12 (305 x 305)
Roof Opening = 14 x 14 (368 x 368)
Shroud Thickness = 0.051 (1.3)
Motor Cover Thickness = 0.040 (1.0)
Curb Cap Thickness = 0.064 (1.6)
^Approximate Unit Weight G/GB = 58/66 lbs. (26/30 kg)
All dimensions in inches (millimeters). *May be greater depending on
motor. ^Weight shown is largest cataloged Open Drip-Proof motor.
1
3
⁄4 (44)
24
3
⁄8
(619)
4
3
⁄8 (111)
*23
3
⁄4
(603)
19
(483)
Roof Downblast Exhaust
Belt & Direct Drive
GB-121 • G-123
Motor HP
Fan
RPM
Static Pressure in Inches wg
Belt Direct 0 0.125 0.25 0.375 0.5 0.625 0.75 1 1.25 1.5
121 123
1/4
VG -Vari-Green is a direct drive brushless DC motor.
580
CFM
704 515
BHP
0.02 0.02
Sones
3.2 3.3
720
CFM
873 735 523
BHP
0.03 0.04 0.04
Sones
4.2 4.3 4.1
C-1/8 860
CFM
1043 932 796 580
BHP
0.05 0.06 0.06 0.06
Sones
5.4 5.5 5.2 5.2
1000
CFM
1213 1119 1013 883 694
BHP
0.08 0.09 0.09 0.10 0.09
Sones
6.7 6.8 6.7 6.4 6.4
B-1/6 1140
CFM
1383 1300 1213 1112 993 831
BHP
0.12 0.13 0.14 0.14 0.14 0.14
Sones
8.4 8.4 8.4 8.1 7.9 7.8
1265
CFM
1535 1460 1384 1299 1204 1093 950
BHP
0.16 0.17 0.18 0.19 0.19 0.20 0.19
Sones
10.2 10.1 10.1 9.9 9.7 9.6 9.4
1395
CFM
1692 1625 1557 1484 1404 1315 1214 907
BHP
0.21 0.23 0.24 0.25 0.26 0.26 0.26 0.24
Sones
12.5 12.4 12.3 12.2 12.0 11.7 11.5 11.3
1/3
1475
CFM
1789 1726 1661 1594 1521 1441 1356 1132
BHP
0.25 0.27 0.28 0.29 0.30 0.31 0.31 0.31
Sones
13.5 13.4 13.3 13.2 13.0 12.7 12.4 12.0
1550
CFM
1880 1820 1759 1696 1629 1555 1475 1289 974
BHP
0.29 0.31 0.32 0.33 0.34 0.35 0.36 0.36 0.33
Sones
14.6 14.5 14.3 14.2 14.0 13.8 13.5 12.9 12.4
1/2
1635
CFM
1983 1926 1868 1810 1747 1680 1608 1446 1231
BHP
0.34 0.36 0.37 0.39 0.40 0.41 0.42 0.43 0.41
Sones
15.9 15.8 15.6 15.4 15.3 15.0 14.8 13.9 13.4
A-1/2 1725
CFM
2093 2038 1984 1928 1871 1810 1743 1600 1426 1180
BHP
0.40 0.42 0.44 0.45 0.46 0.47 0.48 0.50 0.50 0.47
Sones
17.4 17.2 17.0 16.8 16.7 16.4 16.2 15.5 14.9 14.0
C-860-
RPM B-1140-RPM A-1725-RPM VG-1725-RPM
MAXIMUM BHP AT A GIVEN RPM = (RPM/2170)
3
MAXIMUM RPM = 1725
TIP SPEED (ft/min) = RPM x 3.420
MAXIMUM MOTOR FRAME SIZE = 56
VG-
1/2
Direct Drive RPM