Bigassfans Isis User manual

INSTALLATION GUIDE
For help, call 1-877-BIG-FANS
or visit www.BigAssFans.com

Isis®
WWW.BIGASSFANS.COM ©2011 DELTA T CORP. DBA BIG ASS FAN CO. ALL RIGHTS RESERVED
Installation Checklist
Did a structural engineer approve the mounting structure? See page 7 for Big Ass Fans-approved
mounting structures.
Will the fan be installed so that the airfoils are at least 10 ft (3.05 m) above the oor?
Will the fan be installed so that the airfoils have at least 2 ft (0.61 m) of clearance from
obstructions?
Will the fan be installed so that it is not subjected to high winds such as from an HVAC system
or near a large garage door? If the fan is mounted at the same level or higher than a diffuser, the
winglets or airfoil tips must be at a distance that is at least 1x the measure of the fan’s diameter. If the
fan is mounted at the same height or below a diffuser, the winglets or airfoil tips must be at a distance
that is at least 2x the measure of the fan’s diameter.
Will the fan be mounted where it will not come into direct contact with water? The fan should not
be mounted where it will come into direct contact with water unless it is labeled, “Suitable for use in wet
locations.”
Will the distance between multiple fans be at least 2.5x the fans’ diameter when measured from
the centers of the fans?
If you ordered multiple fans, did you keep the parts of each fan together?
What type of circuit does your building structure have, 3-wire or 2-wire? Isis is shipped with a
controller that is compatible with 3-wire circuits. If your building structure includes a 2-wire circuit, the
Limited Access Controller and Remote must be installed with the fan. If you require the Limited Access
Controller and did not note it at the time of order, contact Customer Service at 1-877-BIG-FANS.
Customer Service: 1-877-BIG-FANS
(International: 1-859-233-1271)

i
Isis®
WWW.BIGASSFANS.COM ©2011 DELTA T CORP. DBA BIG ASS FAN CO. ALL RIGHTS RESERVED
2425 Merchant Street
Lexington, KY 40511
1-877-BIG-FANS
www.bigassfans.com
Installation Guide:
Jan. 2013
REV. H
This product was manufactured in a plant
whose Management System is certied as
being in conformity with ISO 9001:2008.
Installation Guide
Isis®
Isis and the Isis logo are trademarks of Delta T Corporation, registered in the United States. All other trademarks used herein are the properties of their
respective owners. The information contained in this document is subject to change without notice. For the most up-to-date information, see the online
Isis Installation Guide at www.bigassfans.com.
May be covered by one or more of the following United States
Patents: 6244821; 6589016; 6817835; 6939108; 7252478; 7284960;
D607988; D587799; 7654798; D642674; 7934907; 8079823; D635237;
D641075; D650893; D642674; 8075273; D650893; 8147182; 8147204;
8152453; and other patents pending.
3187235
Conforms to ANSI/UL STD 507–Electric Fans
Certied to CAN/CSA C22.2 No.113–Fans & Ventilators

IMPORTANT SAFETY INSTRUCTIONS
READ AND SAVE THESE INSTRUCTIONS
TO REDUCE THE RISK OF FIRE, ELECTRIC SHOCK, OR INJURY TO PERSONS, OBSERVE THE FOLLOWING:
CAUTION: Installation work and electrical wiring must be done by qualied person(s) in accordance with all applicable codes
and standards.
CAUTION: When cutting or drilling into wall or ceiling, do not damage electrical wiring and other hidden utilities.
Use this unit only in the manner intended by the manufacturer. If you have questions, contact the manufacturer.
WARNING: Before servicing or cleaning unit, switch power off at service panel and lock the service disconnecting means to
prevent power from being switched on accidentally. When the service disconnecting means cannot be locked, securely fasten
a prominent warning device, such as a tag, to the service panel.
CAUTION: The installation of a Big Ass Fan must be in accordance with the requirements specied in this installation manual
and with any additional requirements set forth by the national electric code (NEC), ANSI/NFPA 70-1999, and all local codes.
Code compliance is ultimately YOUR responsibility!
CAUTION: Exercise caution and common sense when powering the fan. Do not connect the fan to a damaged or hazardous
power source. Do not attempt to resolve electrical malfunctions or failures on your own. Contact Big Ass Fans at 1-877-BIG-
FANS if you have any questions regarding the electrical installation of this fan.
WARNING: To reduce the risk of re, electric shock, and injury to persons, Big Ass Fans must be installed with Big Ass
Fan supplied controllers that are marked (on their cartons) to indicate the suitability with this model. Other parts cannot be
substituted.
CAUTION: When service or replacement of a component in the fan requires the removal or disconnection of a safety device,
the safety device is to be reinstalled or remounted as previously installed.
WARNING: Risk of re, electric shock, or injury to persons during cleaning and user-maintenance! Disconnect the fan from
the power supply before servicing.
CAUTION: Do not bend the airfoils when installing, adjusting, or cleaning the fan. Do not insert foreign objects in between
rotating airfoils.
WARNING: Stay alert, watch what you are doing, and use common sense when installing fans. Do not install fans if tired
or under the inuence of drugs, alcohol, or medication. A moment of inattention while installing fans may result in serious
personal injury.
CAUTION: The installation of this fan requires the use of some power tools. Follow the safety procedures found in the owner’s
manual for each of these tools and do not use them for purposes other than those intended by the manufacturer.
CAUTION: The Big Ass Fans product warranty will not cover equipment damage or failure that is caused by improper
installation.
Leave this installation guide with the owner of the fan after installation is complete.
CAUTION: Do NOT install the fan where it may come into direct contact with water unless the fan is labeled, “Suitable for use
in wet locations.”

Reference Guide
The following is intended as a reference guide. See the referenced pages for complete fan installation and operating instructions.
Mounting the fan If mounting to angle irons, see Mounting Method: Angle Irons on page 9. If mounting in a residential home, see Mounting Method: Wood Frame on page 14. For alternative mounting methods, see page 4.
Airfoil installation See Installing Airfoils on page 23.
Winglet installation See Installing Airfoils on page 23.
Wiring the controller and fan See Electrical Installation on page 25. Mounting the controller See Mounting the Wall Controller on page 28. Operating the fan See Fan Operation on page 29.
Hanging the fan See Hanging the Fan on page 18.
Isis®
WWW.BIGASSFANS.COM ©2011 DELTA T CORP. DBA BIG ASS FAN CO. ALL RIGHTS RESERVED
*Winglets are standard. Airfoil tips are
available as an option. If you purchased the Isis with airfoil tips, they will arrive already installed on the airfoils.

Reference Guide: Mounting
The following is intended as a reference guide for Isis fan mounting methods. See the referenced pages for complete fan installation and operating instructions. Consult a structural engineer to determine which mounting method best suits your building structure. To order optional mounting kits, see the Optional Parts Order Form (p. 37).
I-Beam Z-Purlins Solid Beam
See complete instructions included with the Z-Purlin Installation Kit.
See complete instructions included with the L-Bracket Installation Kit.
See complete instructions included with the I-Beam Adapter Installation Kit.
Angle Irons
See page 9 for mounting instructions.
Isis®
WWW.BIGASSFANS.COM ©2011 DELTA T CORP. DBA BIG ASS FAN CO. ALL RIGHTS RESERVED
Wood Frame Structures
See page 14 for mounting instructions.

Contents
General Information Regulatory Compliance Information i
Important Safety Information ii
Reference Guide iii
Reference Guide (Mounting) iv
Introduction Thank You 1
About Big Ass Fans 1
About this Fan 1
Pre-Installation What’s in the Box 2
Parts Included 3
Alternative Mounting Methods 4
Tools Needed 5
Important Weights 5
Fan Diagram 6
Preparing the Work Site 7
Mounting Method:
Angle Irons 1. Select Proper Angle Irons 9
2. Pre-drill Angle Irons 10
3. Secure Angle Irons (span is longer than 8 ft) 10
4a. Fasten Single Angle Irons to Roof Structure Mounting Points 11
4b. Fasten Double Angle Irons to Roof Structure Mounting Points 12
5. Attach Upper Mount (to Angle Irons) 13
Mounting Method:
Wood Frame 1. Identify Mounting Location 14
2a. Fasten Brackets (to Vaulted Ceiling Beams) 14
2b. Fasten Brackets (to Floor Joists) 15
2c. Fasten Brackets (to Ceiling Joists) 15
3. Attach Mount to Wood Framing Channels 16
4. Fasten Wood Framing Channels (to Brackets) 17
Hanging the Fan 1. Attach Extension Tube (to Upper Mount) 18
2a. Secure Safety Cable (to Angle Irons) 18
2b. Secure Safety Cable (to Safety Clips) 18
2c. Secure Safety Cable (to Wood Frame) 19
3. Attach Main Fan Unit (to Extension Tube) 19
Installing Guy Wires 1. Attach Guy Wire Clamp 20
2. Attach Locking Carabiners to Guy Wire Clamp 21
3a. Attach Beam Clamp (Angle Iron Mounting) 21
3b. Attach Eyebolt (to Wood Frame) 21
4. Route Guy Wire through Gripple®22
5. Install Three Remaining Guy Wires 22
Installing Airfoils 1. Attach Winglets (to Airfoils) 23
2. Position Airfoils 23
3. Attach Airfoils (to Main Fan Unit) 24
Electrical Installation Electrical Installation Safety 25
Power Requirements 25
Wiring: Single Fan Application 26
Wiring: Multi-Fan Application 27
Mounting the Wall Controller 28
Fan Operation Starting, Stopping, and Changing Fan Speed 29
Changing the Fan Direction 29

Contents
Alternative Wiring
Methods Limited Access Application 30
Limited Access Controller and Remote Operation 31
3-Way Single Fan Application 32
Preventive Maintenance Annual Preventive Maintenance 33
General Preventive Maintenance 33
Troubleshooting General Troubleshooting 34
Electrical Troubleshooting 34
Annual Maintenance
Checklist Annual Maintenance Checklist 35
Optional Parts Order
Form Optional Parts Order Form 37
Limited Warranty Warranty Policy 39
Acknowledgment & Return Instructions 43
Warranty Claim Form 45
Responsibility Agreement 46
Big Ass Fan Certied
Installers Check-In Procedure 47
Close-Out Procedure 48

1
Isis®
WWW.BIGASSFANS.COM ©2011 DELTA T CORP. DBA BIG ASS FAN CO. ALL RIGHTS RESERVED
Introduction
About this fan
Note: Fan weight does not include upper mount or extension tube.
Fan diameter Input power Required
circuit size Full load amps Max RPM Airfoil length Fan weight Max fan torque
8 ft (2.4 m) 110–125 VAC/60 Hz 10A 3.9 95 44” (1.11 m) 88 lbs (39.9 kg) 30 ft·lb (40.7 N·m)
10 ft (3 m) 110–125 VAC/60 Hz 10A 3.9 60 56” (1.42 m) 96 lbs (43.5 kg) 30 ft·lb (40.7 N·m)
12 ft (3.7 m) 110–125 VAC/60 Hz 10A 3.9 43 68” (1.72 m) 104 lbs (47.1 kg) 30 ft·lb (40.7 N·m)
Thank you and congratulations on your purchase of a Big Ass Fan, an efcient and cost-effective way to stay cool in the summer and
warm in the winter. The revolutionary design of our fans combines the best of both form and function to bring power performance and a
sleek look to any setting. More importantly, you have purchased a product that is backed by extensive research, thorough testing, and
quality manufacturing. We’re ready to answer any questions or comments at 1-877-BIG-FANS or visit our Web site at
www.bigassfans.com.
Who we are and what we do
Big Ass Fans has been the preeminent manufacturer of large-diameter, low-speed fans since 1999. With a worldwide presence and
located in beautiful Lexington, KY, we research, design, and manufacture the most effective air movement solutions on the market.
Our never-ending commitment to quality and innovation keeps us at the leading edge of a burgeoning industry. With an eye to helping
customers satisfy their needs, and a strong sense of corporate responsibility to the community, Big Ass Fans has redened the way
business is done.

Isis®
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2
What’s in the box
CAUTION: Do not remove the motor from its protective packaging prior to hanging it!
CAUTION: If you ordered multiple fans, be sure to keep the components of each fan together.
The fan is shipped in three labeled boxes. The large, square box contains the main fan unit, upper mount, wall controller, wallplate,
airfoil retainers, airfoil hardware, and winglets. A smaller box contains the airfoils. Another small box contains the extension tube.
Optional parts are shipped in separate boxes that are labeled to identify the contents. If you are missing any piece required for
installation, contact Big Ass Fans at 1-877-BIG-FANS.
Note: Dashed lines indicate internal boxes or bags within the main box. Drawings below are not to scale. All boxes are labeled to
identify the contents.
Main Box1
Hardware
Upper Mount
Main Fan Unit
Wall Controller
Wallplate2
Extension
Tube Box
Extension Tube &
Safety Cable6
Airfoil Box
(10) Airfoil
1. Guy wires (if ordered) are marked and packaged separately within the main box. Brackets for guy wires are included for tubes longer than 4 ft.
2. If installing the fan on a typical lighting circuit with one basic light switch, the Limited Access Controller must be installed.
3. Safety clips and carabiners are only used when the top of the mounting structure is inaccessible.
4. Winglets are standard on Isis fans; however, airfoil tips are available as an option. If you purchased the Isis with airfoil tips, they will arrive already
installed in the airfoils.
5. Optional. The Wood Frame Mounting kit is only included if ordered.
6. 1-ft extension tubes are labeled and packaged in the main box.
(10) Winglet4
Airfoil
Hardware (10) Airfoil
Retainer (2) Safety Clip &
Carabiner3
(8) Square
Washer
Pre-Installation
Wood Frame Mounting
Brackets & Channels
Wood Frame Mounting Box5

3
Isis®
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Parts included
Hardware
Extension Tube Hardware:
(2) 3/8-16 x 3-1/2” Socket Head Cap
Screw
(4) 3/8” Flat Washer
(2) 3/8” Nylock Nut
Main Fan Unit Hardware:
(1) 3/8-16 x 3-1/2” Socket Head Cap
Screw
(1) 3/8” x 3/4” OD x 1/2” Spacer
(2) 3/8” Flat Washer
(1) 3/8” Nylock Nut
Airfoil Hardware:
(20) 5/16-18 x 5/8” Bolt
(20) 5/16” Wave
Washer
Winglet
Hardware:
(10) 10-32 x 1/2”
Screw
Wall Controller3
Wall Controller Wallplate
Mounting methods vary by mounting structure. See the appropriate Mounting Method section for specialized installation instructions.
Note: Drawings below are not to scale.
Upper Mount
Extension Tube &
Safety Cable1Main Fan Unit Wood Frame Mounting
Brackets2Wood Framing Channels2
1. The safety cable is attached to extension tube with a 3/8” bolt and nut.
2. Optional. The Wood Frame Mounting kit is only included if ordered.
3. If installing the fan on a typical lighting circuit with one basic light switch, the LimitedAccess Controller must be installed.
4. Airfoils can be purchased with winglets (standard) or airfoil tips (optional). If you purchased the Isis with airfoil tips, they will arrive already installed in
the airfoils. Winglets are installed on the airfoils during Airfoil Installation.
Airfoils4
(10) Airfoil
(10) Airfoil Retainer (10) Winglet
Mounting
Pre-Installation (cont.)

Isis®
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4
Alternative mounting methods
The following can be purchased for unique residential mounting methods not covered in this manual by lling out the Optional Parts
Order Form (p. 37). Consult a structural engineer prior to fan installation. For more information, contact your Big Ass Fans Sales
Representative or Customer Service at 1-877-BIG-FANS.
The I-beam adapter can be purchased for hanging the Isis from I-beams.
Big Ass Fans offers both a small and large adapter depending on the
width of the I-beam. The I-Beam Adapter can only be used on I-beams
that are 5” (12.7 cm) to 9-7/8” (25 cm) (small adapter) or 9-7/8” (25 cm) to
14-5/8” (37 cm) (large adapter) in width. It is not recommended to mount
the fan from fabricated I-beams. Consult a structural engineer to ensure
your building structure meets the necessary requirements.
I-Beam Adapter
L-Brackets
L-brackets can be purchased for hanging the Isis from structural beams,
such as wooden beams. Slots in the brackets allow for solid beams
with thicknesses ranging from 4” (10.2 cm) to 9” (22.9 cm). Consult a
structural engineer to ensure your building structure meets the necessary
requirements.
Z-Purlin Brackets
Specialized brackets can be purchased for hanging the Isis from building
structures consisting of Z-purlins with lengths ≤30 ft and heights ranging
from 8” (20.3 cm) to 10” (25.4 cm), and spaced ≤5 ft apart. Consult a
structural engineer to ensure your building structure meets the necessary
requirements. Note: Angle irons are not supplied.
Pre-Installation (cont.)

5
Isis®
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Important weights
Part Weight
Upper mount 1.24 lbs (0.56 kg)
Lower mount 1.5 lbs (0.68 kg)
Extension tube (1-ft) 1.21 lbs (0.55 kg)*
Mounting bracket kit 2.54 lbs (1.15 kg)
Tools needed
Big Ass Fans recommends gathering the following tools prior to beginning installation. Note: This list of suggested tools is not
exhaustive. Additional tools may be necessary.
Mechanical installation
Standard wrench set
Standard socket and ratchet set
Torque wrench capable of 25 ft·lb (33.9 N·m)
Phillips and at head screwdrivers
Standard allen wrench set
Drill
Hacksaw
Level
Tape measure
Electrical installation
Phillips and at head screwdrivers
#10 to #14AWG strippers
Medium size channel locks
Multimeter
*Add 3.5 lbs (1.58 kg) for every additional foot of extension tube.
Pre-Installation (cont.)

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6
Fan diagram
Refer to the diagram below to identify the fan components. Note: Fan setup may differ from the illustration depending on the required
mounting method. The safety cable is not pictured below; however, it is an important part of the installation.
A. Upper mount. Secures the fan to the mounting structure.
B. Extension tube. Extends the fan from the ceiling and provides a path for wiring.
C. Main fan unit. Includes motor, hub, lower mount, and power wire.
D. Airfoil. Provides air movement. The unique, patented design provides efcient and effective air movement.
E. Winglet. Improves efciency of the fan. Winglets are standard on Isis fans; however, airfoil tips are available as an option. If you
purchased the Isis with airfoil tips, they will arrive already installed in the airfoils.
Pre-Installation (cont.)

7
Isis®
WWW.BIGASSFANS.COM ©2011 DELTA T CORP. DBA BIG ASS FAN CO. ALL RIGHTS RESERVED
Preparing the work site
When surveying the work site, keep the following mechanical and electrical guidelines in mind.
Mechanical
• A suitable means for lifting the weight of the fan, such as a scissor lift, and at least two installation personnel will be required.
• If hanging the fan from an angle iron, the minimum dimensions of the angle iron must be 2-1/2’’ × 2-1/2’’ × 1/4’’ (6.4 cm × 6.4 cm ×
0.6 cm) and it cannot be longer than 12 ft (3.6 m). It must be secured to the structure. Do not mount the fan to a single purlin, truss,
or bar joist. Consult a structural engineer for installation methods not covered in this manual.
• To reduce the risk of injury to persons, install the fan so that the airfoils are at least 10 ft (3.05 m) above the oor.
• If mounting the fan in the vicinity of an infrared/radiant heater, it is recommended that the fan be mounted outside of the clearances
recommended by the manufacturer of the heater and at a height equal to or above the shielding on the heating element with the
controller on the opposite side of the heater. If mounting the fan below the heater shielding, all fan elements must be outside of
the clearances recommended by the heater manufacturer and the VFD must be remotely mounted. The installation manual for the
specic model of heater will typically provide the minimum clearance to combustibles (MCC).
• Ensure the mounting location will not expose the fan to direct contact with water unless the fan is labeled, “Suitable for use in wet
locations.”
• Adhere to the safety requirements in the table below when selecting where to mount the fan.
Safety requirement Minimum distances
Clearance ≥2 ft from all fan parts. The fan installation area must be free of obstructions such as lights, cables,
sprinklers, or other building structure.
Blade height ≥10 ft above the floor
HVAC equipment ≥1x fan diameter if above diffuser. ≥2x fan diameter if below diffuser. Refer to the illustration below.
Fan spacing 2.5x fan diameter, center-to-center
Radiant/IR heaters See the manufacturer’s requirements for the minimum clearance to combustibles.
Electrical
• Identify the existing wiring to determine which wiring application is needed to install the fan.
• If installing the fan on a typical lighting circuit with one basic light switch in which the critical red conductor or “traveler” is absent, you
will need to purchase the Limited Access Controller. Please discuss this option with your Big Ass Fans representative.
The fan should only be installed according to the instructions described in this manual. Consult a structural engineer
for installation methods not covered in this manual. For optional mounting methods, refer to the installation instructions
included with the fan parts.
Pre-Installation (cont.)
HVAC
Diffuser
HVAC
Diffuser
If the fan is mounted at the same level
or higher than a diffuser, the winglets
must be at a distance that is at least 1x
the measure of the fan’s diameter.
≥1x fan’s diameter
(8 ft)
≥2x fan’s diameter
(16 ft)
8-ft diameter
8-ft diameter
If the fan is mounted below a diffuser,
the winglets must be at a distance that
is at least 2x the measure of the fan’s
diameter.

Notes

9
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1. Select proper angle irons
Follow the table below when selecting angle irons for fan installation. Note: Angle irons and angle iron hardware are not included with
the fan.
Height
Width
Ø 9/16”
(1.4 cm)
Thickness:
1/4” (6 mm)
Angle Iron Side View
(see table for dimensions)
Thickness
Angle iron span
(between mounting points) Minimum angle iron dimensions (W x H x T) Number of angle irons needed
6 ft (1.8 m) or less 2.5” (6.4 cm) x 2.5” (6.4 cm) x 0.25” (0.6 cm) 2
over 6 ft (1.8 m) to 8 ft (2.4 m) 3” (7.6 cm) x 3” (7.6 cm) x 0.25” (0.6 cm) 2
over 8 ft (2.4 m) to 12 ft (3.7 m) 3” (7.6 cm) x 3” (7.6 cm) x 0.25” (0.6 cm) 4*
*Two pairs of angle irons. Pairs should be placed back to back and fastened in center (see step 2).
6’ (1.8m) or less
over 8’ (2.4m) - 12’ (3.7m)
6’ (1.8m) or less
over 6’ (1.8m) - 8’ (2.4m)
over 8’ (2.4m) - 12’ (3.7m)
6’ (1.8m)
or less
over 6’ (1.8m) - 8’ (2.4m)
over 8’ (2.4m) - 12’ (3.7m)
over 6’ (1.8m) - 8’ (2.4m)
Mounting Method: Angle Irons
WARNING: The fan should not be installed unless the structure on which the fan is to be mounted is of sound
construction, undamaged, and capable of supporting the loads of the fan and its method of attachment. A structural
engineer should verify that the mounting structure is adequate prior to fan installation. Verifying the stability of the
mounting structure is the sole responsibility of the customer and/or end user, and Big Ass Fans hereby expressly
disclaims any liability arising therefrom, or arising from the use of any materials or hardware other than those supplied by
Big Ass Fans or otherwise specied in these installation instructions.
CAUTION: Do not install the fan where it will be continuously subjected to external air forces, such as from high winds
or an HVAC system. Big Ass Fans recommends installing the fan at least 2x the fan diameter (center of fan to equipment)
away from any HVAC discharge unit; however, it is the installer’s responsibility to verify the safe performance of the fan
when operated in the intended environment.
CAUTION: Do not install the fan from a single purlin or truss or junction box.
CAUTION: Unsupported angle iron spans should not exceed 12 ft (3.7 m).
CAUTION: Ensure the mounting location will not expose the fan to direct contact with water unless the fan is labeled,
“Suitable for use in wet locations.”

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10 Mounting Method: Angle Irons (cont.)
3. Secure angle irons (if span is longer than 8 ft)
If the angle iron span is 8 ft (2.4 m) or less, proceed to
step 4a on the following page.
If the angle iron span is longer than 8 ft (2.4 m), it is necessary to
use double angle irons.
Locate the center of the angle iron length. Drill Ø 9/16” (1.4 cm) hole
through the center of the vertical wall of the angle iron. Drill a total of
four angle irons.
Place two drilled angle irons back to back. Fasten the angle irons
together with customer-supplied Grade 8 hardware.
Align the angle irons to each other and tighten the bolts to 25 ft·lb
(33.9 N·m) using a 3/4” socket with torque wrench.
Repeat step for remaining two angle irons.
Proceed to step 4b.
Angle Iron Hardware (Customer-Supplied):
a. (2) 1/2-13 Bolt
b. (4) 1/2” Washer
c. (2) 1/2” Nut
Side View
a
b
b
c
2. Pre-drill angle irons
Drill two Ø 9/16”(1.4 cm) holes exactly 5-1/2” (14 cm) apart in the centers of two angle irons.
Measure the distance between the mounting points of the roof structure that the angle irons will span. Measure the same distance on
the angle irons, and drill Ø 9/16” (1.4 cm) holes through each end of the angle irons. Drill holes in two angle irons if span is 8 ft (2.4 m)
or less. Drill holes in four angle irons if span is greater than 8 ft (2.4 m).
Ø 9/16" (1.4 cm)
distance between roof
structure mounting points
5 1/2” (14 cm)
A
1/2 A
Ø 9/16" (1.4 cm)

11
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4a. Fasten single angle irons to roof structure mounting points
If installation requires double angle irons, i.e., span is greater than 8 ft (2.4 m), proceed to step 4b.
CAUTION: The angle irons must be fastened to the roof structure at each end.
Fasten the angle irons to the roof structure mounting points at each end with customer-supplied Grade 8 hardware as shown. Do not
tighten the hardware until the fan has been mounted to the angle irons. Note: Big Ass Fans recommends orienting the angle irons
so that the horizontal legs are facing each other. Refer to the illustration below.
Proceed to step 5.
Angle Iron Hardware (Customer-Supplied):
a. (4) 1/2-13 Bolt
b. (8) 1/2” Washer
c. (4) 1/2” Nut
3”
(7.6 cm)
3”
(7.6 cm)
Ø 9/16”
(1.4 cm)
Thickness:
1/4” (6 mm)
Square Washer
b
a
d
b
c
Mounting Method: Angle Irons (cont.)
Angle Iron Hardware (BAF-Supplied):
d. (8) 3” Square Washer (see diagram)

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12
4b. Fasten double angle irons to roof structure mounting points
CAUTION: The angle irons must be fastened to the roof structure at each end.
CAUTION: The angle irons with fan mounting holes should be positioned on the inside, facing each other.
Fasten the angle irons to the roof structure mounting points at each end with customer-supplied Grade 8 hardware as shown. Do not
tighten the hardware until the fan has been mounted to the angle irons.
Proceed to step 5.
Angle Iron Hardware (Customer-Supplied):
a. (8) 1/2-13 Bolt
b. (16) 1/2” Washer
c. (8) 1/2” Nut
A
3”
(7.6 cm)
3”
(7.6 cm)
Ø 9/16”
(1.4 cm)
Thickness:
1/4” (6 mm)
Square Washer
b
a
d
b
c
Mounting Method: Angle Irons (cont.)
Angle Iron Hardware (BAF-Supplied):
d. (8) 3” Square Washer (see diagram)