Greenheck upblast propeller fans are designed
to discharge contaminants up and away from
the building for most commercial jobs and many
industrial applications. These roof exhaust fans
include both belt and direct drive fans with steel
or aluminum blades. Drive frames and panels
are constructed to match the level of duty and
motor size.
Models RBU and RBUMO are belt drive fans that
offer the ability to adjust fan speed for system
balancing if necessary. These models also offer
flexibility in speeds and motor selections. Model
RBU has the motor in the airstream. Model RBUMO
has the motor out of the airstream, which allows for
high temperature air to be exhausted.
RDU direct drive fans are often preferred for jobs
where maintenance access is difficult. Maintenance
costs are generally lower with direct drive fans since
there are no belts or bearings to replace and no
pulleys to adjust.
• Wide range of construction and performance
capabilities offered, the most complete upblast
propeller fan line available.
• Regardless of fan size, performance or duty level,
all Greenheck Upblast Propeller Roof Fans are
built to perform with the same high standards of
reliability and durability.
• Greenheck subjects these products to extensive
life testing, assuring you that the fans will provide
years of reliable performance.
• Performance as cataloged is assured. All RBU,
RBUMO and RDU models are tested in our AMCA
Accredited Laboratory, and all are licensed to
bear the AMCA Sound and Air Performance seal.
Quick Delivery
and Quick
Build Programs
Greenheck’s Quick Delivery Program
provides many options to help you meet your
project’s schedule. Stocking warehouses and
distribution centers around the world ensure sameday pickup and same-day shipment for orders in by
2 p.m. (CST). Hundreds of custom products can be
manufactured through Quick Build in just days.
For available options and accessories please refer
to the Greenheck Stock & Quick Build Catalog.
Leading Edge
Technical Support
When product and IOM
(Installation, Operation
and Maintenance Manual)
information is needed, our products are supported
by the industry’s best product literature, electronic
media and Computer Aided Product Selection
(CAPS) program. You’ll also find this information on
our Web site at www.greenheck.com
Our national and international representative
organization provide personal service and expertise.
To locate your nearest Greenheck representative,
call 715-359-6171 or visit our Web site at
www.greenheck.com.
Outstanding Customer Service
Greenheck’s experienced staff is ready to
answer your questions and delivers solutions.
Our representatives have a wealth of industry
and product knowledge, they maintain the latest
information and can process orders directly to
our factory.
Count on the personal service and expertise
from our national and international representative
organizations. To locate the Greenheck
representative nearest you, call 715-359-6171 or
visit our Web site at www.greenheck.com
Greenheck Fan Corporation certifies that the RBU,
RBUMO and RDU models shown herein are 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.
RDU, RBU, RBUMO models are
Listed for electrical (UL/cUL 705)
File No. E40001
RBUMO model is Listed for
Emergency Smoke Control Systems
File No. MH17511
Greenheck’s skilled production workers use cost-effective
machines and unique dies designed and built by our own
engineers to add innovative features and greater strength to
our upblast propeller fans. Our advanced manufacturing
processes and quality control procedures always ensure the
highest product quality. And just to be sure you get the peaceof-mind you expect when you specify Greenheck, our assembly
inspectors test run and monitor every fan before it leaves the
factory. Results of these tests are kept in permanent records
for future reference.
3
Page 4
Construction Features
Model RBU (shown) construction features are standard
on all models in this catalog.
10
9
8
7
1
6
11
12
13
1. Windband is heavy–gauge galvanized (or
painted) steel construction with bolted seams.
Edges are reinforced for added strength and
have built–in damper stops.
2. Curb Caps are constructed of galvanized steel
in sizes 18-48. Sizes 54 and 60 are constructed
of painted steel. Curb caps include an integral
venturi inlet and prepunched mounting holes.
2
3
4
5
3. Drive Frames are die formed, galvanized
structural steel to provide a rigid platform for
motors, shafts, bearings and drives.
4. Adjustable Motor Plate
5. Drive Assembly belts, pulleys and keys are
oversized 150% of driven horsepower.
6. Variable Pitch Motor Pulley allows for fan speed
adjustments of 10-15%. Size 42 and larger have
fi xed pulleys.
7. Belts are static–resistant and oil free
8. Bearings: 100% factory tested and designed
specifically for air handling applications with a
minimum L10 life in excess of 100,000 hours
(L 50 life of 500,000 hours).
9. Fan Shaft is precisely sized, ground and
polished so the fi rst critical speed is at least
25% over the maximum operating speed. Where
the shaft makes contact with bearings, close
tolerances result in longer bearing life.
10. Fasteners are corrosion–resistant.
11. Aluminum Butterfl y Dampers provide weather
protection and prevent backdrafts when the
fan is not in operation. Standard damper blade
construction is aluminum with galvanized steel
construction optional.
12. Fan Base and motor cover is constructed of
galvanized steel.
13. Windband Mounting Brackets are designed to
also be used as Lifting Lugs for ease when lifting
unit to the roof deck.
Service Features
Removable Windband. By removing the bolts from
the four windband mounting brackets the windband
can be easily removed. With the windband
removed, access to the fan can be gained through
the butterfly dampers.
Motor out of Airstream, model RBUMO, simplifies
inspection and servicing with the “motor out of the
airstream” design.
Removable Motor Cover enables quick and easy
access to the motor, belt and drives from the
roof deck.
4
Page 5
Accessories
1. Outlet Screen is constructed of heavy–gauge steel
mesh and is available to shield the fan discharge and
dampers from debris. Outlet screens cannot be used
in conjunction with motorized butterfly dampers.
2. Steel Butterfly Dampers are for installations where
standard aluminum construction is not desired. Refer
to notes on performance pages for the minimum
airflow volumes to open dampers.
3. Magnetic Damper Latches are available to minimize
damper flutter when the fan is not in operation.
4. Fusible Link Damper Lifters are available to
automatically open the butterfly dampers when the
air temperature below the damper blades exceeds
165°F (74°C). Fusible links for higher temperatures
are also available. The damper blades are held open
to provide smoke and heat relief with no electrical
power required.
5. Roof Curbs are available to reduce installation time
and costs by ensuring compatibility between the
fan, the curb and the roof opening. All curbs
are lined with fiberglass insulation to prevent
condensation and reduce sound levels. See
Greenheck’s roof curb catalog for complete details.
Aluminum Propellers are available for spark resistance.
Extended Lube Lines for belt driven fans are lubrication
lines with grease fittings that extend from the shaft
bearings to the exterior of the fan base. Extended
lube lines allow for bearing lubrication from the
rooftop without disassembling the fan.
Inlet Guards on model RBUMO fans are
available with protective guards for mounting
to the fan inlet. For models RBU and RDU,
protective guards are available when
mounted within a base extension.
NOTE: When an inlet guard is not ordered
with the fan, it should be provided
by the installer.
Motorized Butterfly Dampers are available for
low CFM applications that insufficiently open the
butterfly dampers, as with 2-speed motors at low
speed. They also assure that the dampers are securely
closed when the fan is not operating.
Painted Exteriors andprotective coatings are offered
to protect the fan from harsh atmospheres where
galvanized steel is not suffi cient. Decorative paints
are available in a variety of colors to match existing
building fi xtures.
Belt Cover or Drive Cover (Belt Tube) is available on
model RBUMO to isolate the drive components from
airstream contaminants.
RBUMO
Inlet Guard
1
2
3
4
5
RBU
Inlet Guard
5
Page 6
High Temperature Options
High Temperature Option
500°F (260°C) for a minimum of 4 hours
1000°F (538°C) for a minimum of 15 minutes
This construction meets specifi cations for IRI
requirements of 500°F (260°C) air for a minimum of
4 hours and the SBCCI “Standard Fire Prevention
Code” requirements of 1000°F (538°C) for a minimum
of 15 minutes in emergency smoke removal
applications. In addition, this construction exceeds
British Standards 7346 Class B (250ºC for 2 hours),
Class C (300°C for 30 minutes) and Class D (300°C
for 1 hour)
ratings are tested in accordance to UL smoke
control systems.
High Temperature Option UL Listed
(Construction Level 2 and Level 3 only)
500°F (260°C) for a minimum of 4 hours
1000°F (538°C) for a minimum of 15 minutes
Snow Load Test for butterfly dampers in UL-793
This construction meets specifi cations for UL Listed
“Power Ventilators for Smoke Control Systems”.
This includes the IRI requirements of 500°F for a
minimum of 4 hours, the SBCCI “Standard Fire
Prevention Code” requirements of 1000°F for a
minimum of 15 minutes and the Snow Load Test
for butterfl y dampers (10 pounds of lifting per
square foot) in UL-793. In addition, this construction
exceeds British Standards 7346 Class B (250°C for
2 hours)
(300°C for 1 hour) temperature requirements.
NOTE: Model RBUMO accommodates airstream
temperatures up to 180°F
temperature features. For continuous high
temperature operation from 180°F (82°C) to
500°F (260°C), use Greenheck model TAUB with
its corresponding high temperature option.
Emergency Smoke Removal
Greenheck model RBUMO can be equipped
for emergency smoke removal applications by
specifying a high temperature option. The table
shows the construction features included with high
temperature options that enable the exhaust of heat
and smoke at 500°F (260°C) for a minimum of
4 hours or 1000°F (538°C) for a minimum of
15 minutes.
temperature requirements. Temperature
, Class C (300°C for 30 minutes) and Class D
(82°C) without high
High temperature testing was conducted at
Greenheck’s research and design facility with
°
airstream temperatures in excess of 1000
F (538°C).
Temperatures were monitored at the following
critical locations throughout the tests: bearings,
bearing compartment, belt tube, motor, motor
compartment, airstream and fan housing.
High
Temperature
Option with
UL/cUL-793*
Features
165°F (74ºC) Fusible link
damper lifters
165°F (74ºC) Fusible link damper lifters that will lift 10 pounds
per square foot
Belt tube with heat shield
Dual drives
High temperature bearings
UL label
(Power ventilators for
smoke control systems)
Construction Level 2 and Level 3 only
*
High
Temperature
Option
6
Page 7
Electrical
Wiring
Wiring from the motor to the disconnect box
is provided when a fan is ordered with a
mounted disconnect.
UL/cUL 705
All model RBU and selected model RDU fans with
TE (Totally Enclosed) motors are available with the
UL/cUL 705 listing for electrical. The UL/cUL 705
listing is available on Model RBUMO fans with ODP
(Open Drip Proof) and TE motors.
RDU, RBU, RBUMO models are Listed
for electrical (UL/cUL 705)
File No. E40001
Motor Selection
Motor frame size, enclosure type and fan size limit
the available standard motor selections. Consult
your local Greenheck representative or the factory
for motor availability.
Disconnect Switches
Toggle type and heavy–duty disconnect switches
are available for positive electrical shut-off
and safety when servicing fans. The following
switches are available to meet individual electrical
requirements and can be factory mounted or
shipped loose for fi eld mounting.
Heavy Duty
NEMA-3R & 4
Toggle
NEMA-7 & 9
NEMA-3R
NEMA-4
• NEMA-3R
Rain-Resistant
• NEMA-4
Watertight
• NEMA-3R &
NEMA-4
Heavy-Duty
• NEMA -7 & 9
for Class 1 and
Class 2 hazardous
locations.
Disconnect Wiring Options
Note: Conduit and wiring by others
Disconnect Installation
RBU with NEMA-3R
Wire on
inside of unit
Disconnect Installation
RBUMO with NEMA-3R
Not recommended for high temperature exhaust
Wire on
outside of unit
Disconnect Installation
RBUMO with NEMA-3R
RBU on a GPI Curb with NEMA-3R
No Tray
RBUMO with GPI and NEMA-3R
RBUMO with GPI and NEMA-3R
7
Page 8
Model Comparison
Direct Drive Fan Selection
These models are designed and constructed for applications with static pressure ranges up to 1 inch wg.
RDU models are available with cast aluminum steel blades. For low sound applications, it is best to select
the largest fan with the lowest RPM to meet the performance requirements. This ensures the tip speeds
will be as low as possible.
Construction Levels
Cast aluminum
airfoil blades
Level 3
Model
Performance Pages
RDU
pages 16-17
Size Range
Diameter
18 to 48 inch
(508 to 1372 mm)
PerformancePropellers
Up to 43,500 cfm
(78,155 m3/hr) and
up to 1 inch wg (249 Pa)
Level 3
Belt Drive Fan Selection Propeller Types
Application requirements for sound and static pressure determine propeller type. Propellers are available
in fabricated steel, fabricated aluminum or cast aluminum.
Construction Levels
Galvanized steel blades
riveted to the hub
Level 1
Model
Performance Pages
pages
18-20 and 23-25
Size Range
diameter
20 to 36 inch
(508 to 1372 mm)
PerformancePropellers
Up to 16,500 cfm
(50,970 m3/hr) and up to
5/8 inch wg (156 Pa)
Level 1
Dual thickness
galvanized steel blades
riveted to the hub
Level 2
Fully welded and
gusseted steel blades
Level 3
Belt Drive Blade Designs
H Type Propeller:
Straight, moderately pitched blade.
It is designed for applications where
static pressures are above 0.5 inch
(125 Pa). These propellers typically
wg
run at higher RPMs and generate
slightly higher sound levels than the
“L” propellers.
8
pages 18-27
pages 18-27
20 to 54 inch
(508 to 1524 mm)
24 to 60 inch
(610 to 1829 mm)
Up to 46,000 cfm
(90,048 m3/hr) and up to
3/4 inch wg (190 Pa)
Up to 64,000 cfm
(149,513 m3/hr) and up to
1 inch wg (249 Pa)
Level 2
Level 3
L Type Propeller:
Swept, steeply pitched blade design.
These propellers typically run at
lower RPMs and generate low sound
levels making them the best selection
for sound critical applications or
applications requiring the best
combination of both air and sound
performance. Typically used when
the static pressure is 0.5 inch wg
(125 Pa) or less.
Page 9
Basics of Fan Selection
The first consideration in any fan selection is the
amount of air to be moved and the resistance to
this air movement. With specific performance
and application criteria in mind, propeller fan
selections typically require decisions based on
the following criteria.
Belt Drive vs. Direct Drive
Belt drive fans offer the ability to adjust fan speed
for system balancing if necessary. They also offer
more flexibility in speeds and motor selections. In
a cost comparison, belt drive fans are typically less
costly than comparable size direct drive fans with
low speed motors.
Direct drive fans are often preferred for jobs where
maintenance access is difficult. Maintenance costs
are generally lower with direct drive fans since there
are no belts or bearings to replace and no pulleys
to adjust.
Larger Fans vs. Smaller Fans
In most applications, several fans may meet the
specified airflow and pressure requirements. Just
as larger fans tend to turn slower and generate
less sound, they also tend to have higher initial
costs but lower operating costs. Smaller fans have
more stable performance curves, lower initial costs,
higher sound levels and higher operating costs
because of their higher speeds.
Low Sound vs. High Static Pressure
Fans selected for high static pressures run at higher
speeds and produce higher tip speeds resulting in
higher sound levels. Conversely, in low pressure
applications fans generally run at lower speeds,
produce lower sound levels and are recommended
for sound sensitive applications.
How Accessories Affect Static Pressure
All accessory losses must be accounted for when
calculating the static pressure load for a fan. This
means upblast propeller roof fans can be specified
with low pressure capabilities, below 3/8 inch wg
(93 Pa), when used in conjunction with properly
applied accessories (as within our installation
recommendations).
When fans are over-specified to compensate for
losses that do not actually exist, both cost and
sound levels can be higher than necessary.
This most commonly results from larger motors
and higher tip speeds.
Motor Service Factor
Upblast roof fan motors (except for the model
RBUMO) are cooled by the airstream. With an
uninterrupted flow of cooling air, motors may be
operated in their service factor range (up to 20%
above the motor nameplate horsepower) without
damage due to overheating. Lesser overloads
are recommended for applications using totally
enclosed or explosion resistant motors.
Belt drive performance tables in this catalog show
RPM selections for each propeller type (L or H) at a
given motor horsepower. The first selection is a 1.0
motor service factor. The second speed selection is
at 1.2 motor service factor. Direct drive performance
tables show Bhp levels with motor service factors
ranging up to 1.2. When a selection using the motor
service factor is not desirable for the application,
specify the next higher motor horsepower.
Propeller Fan Rotation Guide
The propeller blade should cup and throw the air when rotating in the correct rotation as shown below.
• Pillow block bearings are sized for a L10 life in
cap galvanized through size 48. Size 54 and 60 curb
caps are painted steel. Damper blades constructed
of aluminum (galvanized optional).
• Motor plates are adjustable for belt tensioning.
• Drives are sized for a minimum of 150% of
Propeller - RBU & RBUMO - Heavy-duty, welded,
reinforced, steel blades. RDU - Heavy-duty, cast
aluminum blades. All with keyed hubs.
Bearings - Cast iron pillow block bearings with
grease fittings (on RBU and RBUMO).
• Fan shafts are precision turned, ground and
polished steel.
• Motor sheaves are adjustable for system
• Drive belts are static free.
• Motors are heavy-duty ball bearing type.
• Fasteners are corrosion-resistant.
Belt Drive
Shaft
Size
3
⁄4145T182T256343252
excess of 100,000 hours (L50 life of 500,000 hours)
driven horsepower.
balancing(sizes 42 and larger are fi xed pitch).
Max Motor
Frame Size
Belt
Drive
Direct
Drive
Approximate
Weight* (lbs.)
RBURBUMORDU
Model RGU, Upblast Ventilator
Model RGU is designed for use as a
weatherproof outlet on vertical high
velocity exhaust systems and can be
furnished without the curb cap for
mounting directly on round stacks.
Standard construction is heavy-gauge
galvanized steel. Nine sizes are available,
corresponding to powered units in
sizes 18-60.
Fusible link damper lifters are available to
allow RGU units to function as heat and
smoke relief vents.
Shown below is a portion of a typical performance
table used in this catalog. Performance data shown,
offers the best selections for each propeller type
(“L” or “H”) relative to sound, RPM and
static pressure.
Most sidewall applications can be met with the “L”
type propeller. When using the performance tables,
look first at the “L” selections, because they offer
the lowest speed and sound levels.
Model Number
Level 1 PerformanceMax RPM L - 1085 H - 1221Max Motor Frame Size - 56TS = RPM x 5.235
RBU-1L20-41/4
“L” type
Low pressure
RBU-1H20-41/4
propeller
“H” type
RBU-1L20-31/3
High pressure
RBU-1H20-31/3
propeller
RBU-1L20-51/2
RBU-1H20-51/2
Shows level of construction
based on fan RPM &
motor frame size. See
Performance Charts.
Note that each max.
BHP is cataloged at
a 1.0 and 1.2 service
factor. See page 9.
CFM / Static Pressure in Inches WG
Optimum selection
range for the “L”
type propeller.
Optimum selection
range for the “H”
type propeller.
CFM values shown
in black are the
most efficient
selections. Values
shown in gray are
not recommended.
14
Page 15
Model Number Codes
Direct Drive
Model Number Code - Direct Drive
The model number code is designed to completely identify the fan.
A detailed explanation of the RDU model number is shown below.
RDU - 36 - 6 18 - B 30
Direct Drive
Upblast Propeller
Roof Fan
Fan Size
Number of Blades
Blade Pitch
Motor RPM
A = 1750
B = 1160
C = 860
F = 680
Motor HP
4 = ¼ 10 = 1 30 = 3
3 = ¹/³ 15 = 1½ 50 = 5
5 = ½ 20 = 2 75 = 7½
7 = ¾
Model Number Code - Belt Drive
The model number system is designed to
completely identify the fan. The correct code
letters must be specifi ed to designate motor in
airstream or motor out of airstream. The remainder
of the model number is determined by the size and
performance selected from the following pages.
A detailed explanation of the model number code
is shown below.
RBU MO - 2 H 36 - 10
Belt Drive
Upblast Propeller
Roof Fan
Motor out of Airstream
Level of
Construction 1, 2, 3
Propeller Type
L-Low
H-High
Fan Size
RBU
Motor in Airstream
Motor Horsepower
4 = ¼ 20 = 2
3 = ¹/³ 30 = 3
5 = ½ 50 = 5
7 = ¾ 75 = 7½
10 = 1 100 = 10
15 = 1½
150 = 15
All propellers for model
RDU fans are of cast
aluminum construction.
Performance certified is for Model RDU exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
Performance certified is for Model RDU exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
17
Page 18
RBU-20 Belt Drive
Model Number
Level 1 PerformanceMax RPM L - 1084 H - 1443Max Motor Frame Size - 56TS = RPM x 5.236
Performance certified is for Model RBU exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
type A: free inlet hemispherical sone levels. The AMCA Certified Ratings Sound Seal applies to sone ratings only.
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
18
Page 19
RBU-30 Belt Drive
Model Number
Level 1 PerformanceMax RPM L - 695 H - 963Max Motor Frame Size - 56TS = RPM x 7.854
Performance certified is for Model RBU exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
19
Page 20
RBU-36 Belt Drive
Model Number
Level 1 PerformanceMax RPM L - 551 H - 806Max Motor Frame Size - 145TTS = RPM x 9.424
Performance certified is for Model RBU exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
20
Page 21
RBU-42 Belt Drive
Model Number
Level 2 PerformanceMax RPM L - 718Max Motor Frame Size - 184TTS = RPM x 10.995
Performance certified is for Model RBU exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
Minimum CFM required
to open dampers
Aluminum Dampers: 24820
Steel Dampers: 24820
CFM values shown in
black are the most efficient
selections. Values shown in
gray are not recommended.
Performance certified is for Model RBU exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
22
Page 23
RBUMO-20 Belt Drive
Model Number
Level 1 PerformanceMax RPM L - 1060 H - 1393 Max Motor Frame Size - 56TS = RPM x 5.236
RBUMO-1L20-41/47300.1811.23303
RBUMO-1L20-41/48150.2513.23688
RBUMO-1L20-41/48420.2813.93810
RBUMO-1L20-31/38970.3315.040593268
RBUMO-1L20-31/39260.3615.541903442
RBUMO-1H20-31/311380.3017.03217
RBUMO-1H20-31/311780.3317.33330
RBUMO-1H20-31/312160.3617.63437
RBUMO-1L20-51/210270.5017.64647397038043539
RBUMO-1L20-51/210600.5518.34797413939793754
RBUMO-1H20-51/213490.5018.93813342533393252
RBUMO-1H20-51/213930.5519.639373559347533913224
Level 2 PerformanceMax RPM L - 1214 H - 1594 Max Motor Frame Size - 145TTS = RPM x 5.236
Performance certified is for Model RBUMO exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
23
Page 24
RBUMO-30 Belt Drive
Model Number
Level 1 PerformanceMax RPM L - 696 H - 929 Max Motor Frame Size - 56TS = RPM x 7.854
RBUMO-1L30-31/34810.3011.36936
RBUMO-1L30-31/34960.3311.67153
RBUMO-1L30-31/35120.3612.17383
RBUMO-1H30-31/36030.3012.66634
RBUMO-1H30-31/36230.3413.26854
RBUMO-1H30-31/36400.3613.77041
RBUMO-1L30-51/25700.5013.7822067876349
RBUMO-1L30-51/25880.5514.28480709766966238
RBUMO-1H30-51/27190.5016.87910691566696422
RBUMO-1H30-51/27350.5517.58086711368716630
RBUMO-1L30-73/46520.7517.29403818078427486
RBUMO-1L30-73/46730.8217.997058529820278757064
RBUMO-1H30-73/48140.7521895680827857763971946644
RBUMO-1H30-73/48440.8223928684458228801575947088
RBUMO-1L30-10
RBUMO-1H30-10
RBUMO-1H30-10
Level 2 PerformanceMax RPM L - 933 H - 1167 Max Motor Frame Size - 184TTS = RPM x 7.854
RBUMO-2L30-10
RBUMO-2L30-10
RBUMO-2H30-10
RBUMO-2H30-10
RBUMO-2L30-15
RBUMO-2L30-15
RBUMO-2H30-15
RBUMO-2H30-15
RBUMO-2L30-20
RBUMO-2L30-20
RBUMO-2H30-20
RBUMO-2H30-20
Level 3 PerformanceMax RPM L - 1109 H - 1420 Max Motor Frame Size - 184TTS = RPM x 7.854
Minimum CFM required
to open dampers
Aluminum Dampers: 6050
Steel Dampers: 7130
CFM values shown in
black are the most efficient
selections. Values shown in
gray are not recommended.
Performance certified is for Model RBUMO exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
24
Page 25
RBUMO-36 Belt Drive
Model Number
Level 1 PerformanceMax RPM L - 551 H - 784 Max Motor Frame Size - 145TTS = RPM x 9.424
Performance certified is for Model RBUMO exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
25
Page 26
RBUMO-42 Belt Drive
Model Number
Level 2 PerformanceMax RPM L - 701 Max Motor Frame Size - 184TTS = RPM x 10.995
CFM values shown in
black are the most efficient
selections. Values shown in
gray are not recommended.
Performance certified is for Model RBUMO exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
26
Page 27
RBUMO-54 Belt Drive
Model Number
Level 2 PerformanceMax RPM H - 585 Max Motor Frame Size - 184TTS = RPM x 14.135
black are the most efficient
selections. Values shown in
gray are not recommended.
Performance certified is for Model RBUMO exhaust for installation type A: Free inlet, Free outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include
appurtenances (accessories). The sound ratings shown are loudness values in fan sones at 5 ft. (1.5m) in a hemispherical free field calculated per AMCA Standard 301. Values are for installation
free inlet hemispherical sone levels.
type A:
*Sones shown apply to the highest cataloged CFM in black type at each fan RPM. For selections at other CFM and static pressure points, refer to the CAPS program.
The AMCA Certified Ratings Sound Seal applies to sone ratings only.
27
Page 28
Specifications
BELT DRIVE
Belt driven, axial type upblast propeller roof exhaust
fans shall be provided as follows:
Propellers shall be constructed with fabricated
steel, fabricated aluminum or cast aluminum blades
and hubs. Propellers shall be securely attached
to fan shafts. All propellers shall be statically and
dynamically balanced. Motors shall be heavy duty
type, matched to the fan load and furnished at the
specified voltage, phase and enclosure. Ground and
polished steel fan shafts shall be mounted in ball
bearing pillow blocks. Bearings shall be selected
for a minimum L
(L50 average life of 500,000 hours) at maximum
cataloged operating speeds. Drives shall be sized for
a minimum of 150% of driven horsepower. Pulleys
shall be of the fully machined cast iron type, keyed
and securely attached to the wheel and motor
shafts. Motor sheaves shall be adjustable for final
system balancing. Drive frame assemblies shall be
galvanized steel or painted steel. Drive frames shall
have formed channels and fan panels shall have
a deep formed inlet venturi. Windbands shall be
constructed of heavy gauge galvanized steel with
reinforced edges and bolted seams. Curb caps shall
be constructed of galvanized steel in sizes 20-48
(sizes 54 and 60 constructed of painted steel). The
axial belt drive upblast propeller roof fans shall bear
the AMCA Certified Rating Seals for both sound and
air performance.
For RBUMO models, fans shall meet the following
additional requirements: Motors shall be mounted out
of the airstream. Motor covers shall be vented
for motor cooling.
For high temperature applications, insert the
appropriate option shown below.
HIGH TEMPERATURE OPTION
This construction meets specifications for IRI
requirements of 500ºF
4 hours and the SBCCI “Standard Fire Prevention
Code” requirements of 1000ºF (538ºC) for a
minimum of 15 minutes in emergency smoke
removal applications.
life in excess of 100,000 hours
10
(260ºC) air for a minimum of
In addition, this construction exceeds British
Standards 7346 Class B (250ºC for 2 hours),
Class C (300ºC for 30 minutes), and Class D
(300ºC for 1 hour) temperature requirements.
Temperature ratings tested in accordance to
UL smoke control systems.
HIGH TEMPERATURE OPTION - UL LISTED
This construction meets specifications for UL
Listed “Power Ventilators for Smoke Control
Systems”. This includes the IRI requirements of
500ºF
(260ºC) for a minimum of 4 hours, the SBCCI
“Standard Fire Prevention Code” requirements
of 1000ºF (538ºC) for a minimum of 15 minutes,
and the Snow Load Test for butterfly dampers
in UL-793. In addition, this construction exceeds
British Standards 7346 Class B (250ºC for 2 hours),
Class C (300ºC for 30 minutes), and Class D
(300ºC for 1 hour) temperature requirements.
Fans shall be Model RBU/RBUMO as
manufactured by Greenheck Fan Corporation,
in Schofield, Wisconsin.
DIRECT DRIVE
Direct driven, axial type upblast propeller roof
exhaust fans shall be provided as follows:
Propeller construction shall be cast aluminum airfoil
design. A tapered bushing shall lock the propeller
to the motor shaft. Propellers shall be statically and
dynamically balanced for vibration free operation.
Motors shall be heavy duty type, matched to the fan
load and furnished at the specified voltage, phase
and enclosure. Motor, drive frame and fan panel/curb
cap assemblies shall be galvanized steel or painted
steel. Drive frames shall have formed channels and
fan panel/curb cap shall have a deep formed inlet
venturi. Windbands shall be constructed of heavy
gauge galvanized steel with reinforced edges and
bolted seams. The axial direct drive upblast propeller
roof fans shall bear the AMCA Certified Rating Seals
for both sound and air performance.
Fans shall be Model RDU as manufactured by
Greenheck Fan Corporation, in Schofield, Wisconsin.
Our Warranty
Greenheck warrants this equipment to be free from defects in material and workmanship for a period
of one year from the shipment date. Any units or parts which prove defective during the warranty
period will be replaced at our option when returned to our factory, transportation prepaid. Motors are
warranted by the motor manufacturer for a period of one year. Should motors furnished by Greenheck
prove defective during this period, they should be returned to the nearest authorized motor service
station. Greenheck will not be responsible for any removal or installation costs.
As a result of our commitment to continuous improvement, Greenheck reserves the right to change