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)
RPM (Belt)
RPM (Direct)
RPM (Vari-Green)
HP
Density 0.075 lb/ft
3
Density 1.2 kg/m
3
25
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.
Roof Downblast - Exhaust
Belt & Direct Drive
GB-141 • G-143
1
3
⁄4 (44)
Damper Size = 16 x 16 (406 x 406)
Roof Opening = 18 x 18 (470 x 470)
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 = 77/86 lbs. (35/39 kg)
All dimensions in inches (millimeters). *May be greater depending on
motor. ^Weight shown is largest cataloged Open Drip-Proof motor.
28
3
⁄8
(721)
4 (102)
*23
3
⁄4
(603)
22
(559)
Motor HP
Fan
RPM
Static Pressure in Inches wg
Belt Direct 0 0.125 0.25 0.375 0.5 0.75 1 1.25 1.5 1.75
141 143
1/4
VG -Vari-Green is a direct drive brushless DC motor.
580
CFM
1076 855
BHP
0.04 0.04
Sones
4.7 4.7
720
CFM
1336 1169 938
BHP
0.07 0.08 0.08
Sones
5.8 5.9 5.2
C-1/8 860
CFM
1595 1457 1304 1085
BHP
0.12 0.13 0.13 0.13
Sones
7.1 7.0 6.6 6.1
950
CFM
1762 1636 1506 1344 1085
BHP
0.16 0.17 0.18 0.18 0.17
Sones
8.1 8.0 7.6 7.1 6.5
1075
CFM
1994 1882 1771 1647 1490
BHP
0.24 0.25 0.26 0.26 0.26
Sones
10.0 9.9 9.4 8.9 8.4
1/3 B-1/3 1140
CFM
2115 2008 1905 1792 1660 1233
BHP
0.28 0.30 0.31 0.31 0.31 0.29
Sones
11.0 10.9 10.4 9.9 9.4 8.2
1/2
1265
CFM
2347 2250 2158 2062 1955 1677 1048
BHP
0.39 0.40 0.41 0.42 0.42 0.42 0.35
Sones
12.9 12.7 12.3 11.9 11.4 10.4 8.8
1360
CFM
2523 2433 2347 2259 2166 1943 1602
BHP
0.48 0.50 0.51 0.52 0.52 0.53 0.51
Sones
14.6 14.3 13.9 13.5 13.1 12.2 11.0
3/4
1450
CFM
2690 2606 2524 2443 2358 2165 1905 1501
BHP
0.58 0.60 0.61 0.63 0.63 0.64 0.63 0.59
Sones
16.2 15.9 15.6 15.2 14.7 13.8 12.9 11.7
1550
CFM
2875 2797 2719 2644 2566 2396 2191 1910 1297
BHP
0.71 0.73 0.74 0.76 0.77 0.78 0.79 0.76 0.65
Sones
17.7 18.0 17.4 17.2 16.8 15.0 14.8 14.8 14.9
1 A-1 1725
CFM
3200 3129 3059 2991 2923 2782 2619 2427 2184 1815
BHP
0.98 1.00 1.02 1.03 1.05 1.07 1.07 1.09 1.06 1.00
Sones
20.0 21.0 20.0 19.9 19.6 18.5 17.2 17.0 16.8 16.7
C-860-
RPM B-1140-RPM A-1725-RPM VG-1550-RPM
MAXIMUM BHP AT A GIVEN RPM = (RPM/1676)
3
MAXIMUM RPM - GB-141=1725, G-143=1725
TIP SPEED (ft/min) = RPM x 3.829
MAXIMUM MOTOR FRAME SIZE = 145T
VG-
3/4
Direct Drive RPM
