Cumberland Mega-Flow External Damper Series User manual

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 1 of 24
Mega-Flow External Damper Fan
Unassembled
Owner’s Manual
Cumberland
1004 E. Illinois St.
Assumption, IL 62510

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 2 of 24
Table of Contents
Section Description Page
1. Limited Warranty...........................................................................................................................................3
2. Warnings.......................................................................................................................................................4
3. External Damper Fan Mounting Dimensions ................................................................................................5
4. Assemble Fan ...............................................................................................................................................6
5. Assemble Cone...........................................................................................................................................12
5.1 Tab Cone Assembly............................................................................................................................13
6. Attach Cone.................................................................................................................................................15
7. Attach the Damper ......................................................................................................................................16
8. Attach the Outside Fan Guard ....................................................................................................................17
8.1 36”, 48”, 52” and 54” Fan PVC-Coated Guard Assembly...................................................................17
8.2 54” Fan Guard Assembly ....................................................................................................................17
9. Attach the Door Stop Assembly..................................................................................................................18
9.1 36”, 48”, 52”, and 54” Bumper Rod Door Stop Assembly...................................................................18
10. Inside Wire Guard ....................................................................................................................................19
10.1 Wire Guard Cut-Out for Motor.............................................................................................................19
10.2 Wire Guard Installation........................................................................................................................19
11. Fan Description Tree................................................................................................................................21
12. Replacement Parts –Motors and Sheaves..............................................................................................22

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 3 of 24
Limited Warranty
1. Limited Warranty
The GSI Group, LLC. (“GSI”) warrants products which it manufactures to be free of defects in materials and
workmanship under normal usage and conditions for a period of 12 months after sale to the original end-user or if a
foreign sale, 14 months from arrival at port of discharge, whichever is earlier. The end-user’s sole remedy (and GSI’s
only obligation) is to repair or replace, at GSI’s option and expense, products that in GSI’s judgment, contain a
material defect in materials or workmanship. Expenses incurred by or on behalf of the end-user without prior written
authorization from the GSI Warranty Group shall be the sole responsibility of the end-user.
Warranty Extensions:The Limited Warranty period is extended for the following products:
Product
Warranty Period
AP Fans and
Flooring
Performer Series Direct Drive
Fan Motor
3 Years
All Fiberglass Housings
Lifetime
All Fiberglass Propellers
Lifetime
AP/Cumberland
Flex-Flo/Pan Feeding Systems
2 Years
Cumberland
Feeding/Watering
Systems
Feeder System Pan Assemblies
5 Years **
Feed Tubes (1.75" & 2.00")
10 Years *
Centerless Augers
10 Years *
Watering Nipples
10 Years *
Grain Systems
Grain Bin Structural Design
5 Years
Grain Systems
Farm Fans
Zimmerman
Portable & Tower Dryers
2 Years
Portable & Tower Dryer Frames
and Internal Infrastructure †
5 Years
GSI further warrants that the frame, basket and excluding all auger and auger drive components of the portable and
tower dyer shall be free from defects in materials for a period of time beginning on the twelfth (12th) month from the date
of purchase and continuing until the sixtieth (60th) month from the date of purchase (extended warranty period). During
the extended warranty period, GSI will replace the frame or basket components that prove to be defective under normal
conditions of use without charge, excluding the labor, transportation, and/or shipping costs incurred in the performance
of this extended warranty.
Conditions and Limitations:
THERE ARE NO WARRANTIES THAT EXTEND BEYOND THE LIMITED WARRANTY DESCRIPTION SET FORTH
ABOVE. SPECIFICALLY, GSI MAKES NO FURTHER WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING, WITHOUT LIMITATION, WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE OR USE IN CONNECTION WITH: (i) PRODUCT MANUFACTURED OR SOLD BY GSI OR (ii) ANY
ADVICE, INSTRUCTION, RECOMMENDATION OR SUGGESTION PROVIDED BY AN AGENT, REPRESENTATIVE
OR EMPLOYEE OF GSI REGARDING OR RELATED TO THE CONFIGURATION, INSTALLATION, LAYOUT,
SUITABILITY FOR A PARTICULAR PURPOSE, OR DESIGN OF SUCH PRODUCTS.
GSI shall not be liable for any direct, indirect, incidental or consequential damages, including, without limitation, loss of
anticipated profits or benefits. The sole and exclusive remedy is set forth in the Limited Warranty, which shall not exceed
the amount paid for the product purchased. This warranty is not transferable and applies only to the original end-user.
GSI shall have no obligation or responsibility for any representations or warranties made by or on behalf of any dealer,
agent or distributor.
GSI assumes no responsibility for claims resulting from construction defects or unauthorized modifications to products
which it manufactured. Modifications to products not specifically delineated in the manual accompanying the equipment
at initial sale will void the Limited Warranty.
This Limited Warranty shall not extend to products or parts which have been damaged by negligent use, misuse,
alteration, accident or which have been improperly/inadequately maintained. This Limited Warranty extends solely to
products manufactured by GSI.
Prior to installation, the end-user has the responsibility to comply with federal, state and local codes which apply to the location and
installation of products manufactured or sold by GSI.
* Warranty prorated from list price:
0 to 3 years –no cost to end-user
3 to 5 years –end-user pays 25%
5 to 7 years –end-user pays 50%
7 to 10 years –end user pays 75%
** Warranty prorated from list price:
0 to 3 years –no cost to end-user
3 to 5 years –end-user pays 50%
†Motors, burner components and
moving parts not included. Portable
Dryer screens included. Tower Dryer
screens not included.

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 4 of 24
2. Warnings
Warning!
Disconnect All Power Sources Before Installing This Equipment. Failure To Disconnect Power Source Can
Result In Property Damage, Serious Injury Or Death!
Warning!
Dangerous Rotating Machinery! Keep Hands, Clothing, Etc. Clear When Operating!
Do Not Operate Without All Guards And Covers In Place!
Warning!
All Wiring Should Be In Accordance with National Electrical Codes Or Other Local Codes.
Warning!
The Installer Is Responsible For Complying With All Relevant Regulations, Such As National Wiring
Regulations And Accident Prevention Regulations. Particular Attention Must Be Given To The Cross-
sectional Areas Of Conductors, The Selection Of Fuses Or Other Protection, And Protective Earth/Ground
Connections!
Warning!
The Voltages In The Power Cables And Certain Parts Of The Drive Can Result In Death. Whenever The
Drive Has Been Used It Must Be Isolated And Disconnected For 5 Minutes Before Any Work Commences
Danger!
Only Qualified Electrical Personnel Familiar With The Construction And Operation Of This Equipment And
The Hazards Involved Should Install, Adjust, And/Or Service This Equipment. Read And Understand This
Manual In Its Entirety Before Proceeding. Failure To Observe This Precaution Could Result In Severe
Bodily Injury Or Death!
!
!
!
!
!
!
!
!
!

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 5 of 24
Diagram 2: 36”, 48”, & 52” Fan Spacing with Cone
3. External Damper Fan Mounting Dimensions
Diagram 1: Framing Diagram
See Fan Spacing
Dimensions in
Diagrams 2 and 3
Below.
INTAKE
SIDE
EXHAUST
ORIFICE
SIDE
Width
Rough Opening
Height
Fan Size
Fan Model
Width
Height
36"
Mega Flow External Damper
43.00” (109.22 cm)
43.00” (109.22 cm)
48”
Mega Flow External Damper
55.00” (139.70 cm)
55.00” (139.70 cm)
52"
Mega Flow External Damper
57.00” (144.78 cm)
57.00” (144.78 cm)
54"
Mega Flow External Damper
60.88” (154.62 cm)
60.88” (154.62 cm)
Fan Housing
Cone
Center-to-Center
Spacing
Fan Size
Spacing
36"
50" (127.0 cm)
48"
63” (160.1 cm)
52”
68” (172.7cm)
Diagram 3: 54” Fan Spacing with Cone
Fan Size
Spacing
Spacing (Sides Flattened)
54”
75” (190.5 cm)
67” (170.2 cm)
Fan Housing
Cone

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 6 of 24
CAP Screw
3/8” x 16 x 1 1/2”
(1004-3054)
Flat Washer
3/8” X 1
(1003-1462).
Pillow
Bearing
(1016-0100)
Pillow Bearing
Mount
(0404-5104)
Lock Nut
3/8” x 1
(1001-1457)
Shaft Coated
1 x 7 5/8
(6403-2110)
Sheave 8.4 Fenner
(1011-5002 –
MF-36ED)
Sheave 10.4 Fenner
(1011-5000 –MF-48ED
THRU MF-54ED)
Key Shear
(1019-2417)
TOOLS REQUIRED
Ratchet
Torque wrench
Flat head screwdriver
6" (152 mm) Ratchet extension
5/32" (4 mm) Allen head socket
Pop rivet gun
9/16" (14 mm) socket
1/8" (3 mm) Allen head socket
9/16" (14 mm) open end box end wrench
7/16" (11 mm) socket
Rubber mallet
7/16" (11 mm) open end box end wrench
1/2" (13 mm) socket
2' (61 cm) scale or carpenter's square
Needle nose pliers
Electric or cordless drill
3/8" (10 mm) Socket -12pt. star
Thread Locking Compound (LOCKTITE®)
3/8" (10 mm) Socket head bit
Phillips head screwdriver
4. Assemble Fan
1. Refer to Figure 1. Assemble the Pillow Block Bearings (1016-0100) to the Pillow Bearing Mount
(0404-5104) with four Cap Screws (1004-3054), Flat Washers (1003-1462) and Lock Nuts (1001-1457)
as shown.
2. Refer to Figure 1. Insert the Key Shear (1019-2417) into the Shaft (6403-2110). Slide Prop Pulley
onto shaft until Pulley is flush with the end of the shaft. MAKE SURE SET SCREW SIDE OF
PULLEY IS TOWARD SHAFT. Put 2-3 drops of Thread locking compound on the pulley set screw.
Tighten set screw of pulley. Recommended torque is 110 in. lbs.
3. Insert shaft assembly into the bearing pillows as shown in Detail A.Slide shaft assembly into bearings to a
distance of 1.5" (3.81 cm) between the flange on the bearing pillow and the pulley as shown in Detail A.
Lightly tighten the lock screws on the pillow bearings.
Warning!
Do Not Connect Electrical Power Until Assembly Is Complete
Always Double Check Power Sources!
Figure 1: Pillow Bearing/Mount Plate Assembly
!

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 7 of 24
Detail A
1.5"
4. Refer to Figure 2. Assemble the Top and Bottom Vertical Mounting Braces (0404-7587) and the Pillow Block
Bearing Assembly to the two Vertical Members (0404-8284). Secure with 3/8" x 16 x 1 Bolts (1002-2374) and
3/8" Lock Nuts (1001-1457).
Top Vertical Mounting Bracket
(0404-7587) 52” and 54” Fans
Only
Bearing Pillow
Assembly
Lock Nut 3/8”
(1001-1457)
Motor Mounting
Bracket
(0404-3700)
Bolt
3/8-16x1
(1002-2374)
Sheave Idler
Assembly
(1011-9005)
Screw
3/8-16 1
(1004-1426)
Bolt
3/8-16 x1
(1002-2374)
Lock Nut 3/8”
(1001-1457)
Vertical Member
(0404-8284)
Figure 2: Internal Fan Assembly
Bottom Vertical Mounting Bracket
(0404-7587). 52” and 54” Fans Only.
Vertical Member
(Part number varies
with fan size)
Shaft Flush with Inside of Hub
Shaft Flush Sheave
Prop Spider
(Blades not Shown)
Set Screw

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 8 of 24
5. Install the Sheave Idler Assembly (Belt Tensioner) (1011-9005) using Screw (1004-1426). See Figure 2. Do
not tighten down screw. See Step 13 for correct orientation.
6. Refer to Figure 3.Assemble the Side Panels, the Top Panel and the Bottom Panel to the Orifice using 32 Fan
Screws (1004-8030).
7. 36” and 48” Fans: Refer to Figure 3. Attach the internal fan assembly to the inside face of the orifice at top
and bottom. Attach cone support bracket to top panel using bolts (1002-2374) and lock nuts (1001-1457).
8. 52” and 54” Fans: Refer to Figure 4. Attach the Internal Fan Assembly to the bottom Fan Cabinet using Bolt
(1002-2374) and Lock Nuts (1001-1457). Attach the Cone Support Bracket and internal fan assembly to the top
Panel with the same type bolts.
9. Attach the two Tension Latches (1040-0105) to the right and left side panels with rivets. Refer to Figure 3.
10. Refer to Figure 3. Attach the three Blade Prop using Key Shear (1019-2417). Align the Discharge tip of the
blade with the edge of the orifice.

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 9 of 24
1004-8030 #14x1/2" TRUSS SCREW
MF-36ED - 0404-10053
MF-36ED - 0404-10047
1002-2374 3/8-16x1" CARRAGE BOLT
CONE SUPPORT BRACKET 1001-1457 3/8-16 LOCK NUT
MF-36ED - 6403-9202 4 BLADE
1019-2417 1/4x 1/4x1" KEY SHEAR
MOTOR/SHEAVE
1002-2373
5/16-18x3/4
CARRIAGE BOLT
1022-3107 COG BELT
1040-0105 TENSION DRAW LATCH
1005-5006 3/16 AD62 RIVET
MF-36ED - 0404-10056
1001-1735 5/16-18 LOCK NUT
INTERNAL BELT TENSIONER ASSEMBLY
MF-36ED 0404-10054
MF-36ED 0404-10055
ORIFICE
MF-48ED - 0404-10318
LH SIDE PANEL
MF-48ED - 0404-10319
SEE CHART
BOTTOM PANEL
MF-48ED 0404-10322
RH SIDE PANEL
MF-48ED 0404-10320
GALVANIZED PROP
MF-48ED - 6403-5010 3 BLADE
MF-36ED - 0404-10246 MF-48ED - 0404-10362
TOP PANEL
MF-48ED - 0404-10312
Figure 3: External Damper Fan Assembly 36” and 48”

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 10 of 24
MF-54ED - 0404-10787
MF-54ED - 0404-10648
MF-54ED - 0404-10786
MF-54ED 0404-10788
MF-52ED - 0404-8257 MF-54ED - 0404-10362
MF-54ED - 6403-5020
MF-54ED 0404-10785
1004-8030 #14x1/2" TRUSS SCREW
MF-52ED - 0404-8256
MF-52ED - 0404-8300
1005-5006 3/16 AD62 RIVET
SEE CHART
1040-0105 TENSION DRAW LATCH
1002-2373
5/16-18x3/4
CARRIAGE BOLT
1022-3107 COG BELT
1001-1735 5/16-18 LOCK NUT
INTERNAL BELT TENSIONER ASSEMBLY
1001-1457 3/8-16 LOCK NUT
MF-52ED 0404-7551
MF-52ED 0404-7551
0006-5028 5/16" PLASTIC PLUG
1019-2417 1/4x 1/4x1” KEY SHEAR
MF-52ED - 6403-5017
1002-2374 3/8-16x1" CARRAGE BOLT
MF-52ED - 0404-7552
CONE SUPPORT BRACKET
ORIFICE
LH SIDE PANEL
GALVANIZED PROP
TOP PANEL
MOTOR/SHEAVE
BOTTOM PANEL
RH SIDE PANEL
Figure 4: External Damper Fan Assembly 52” and 54”

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 11 of 24
Figure 6: Install Belt
Belt
Tensioner
Straight Edge
Fan Pulley
11. Refer to Detail A. Put 2-3 drops of thread locking compound on the prop set screw. Use a 12 point socket to
tighten the prop set screw. Recommended torque of set screw is 110 in. lbs.
12. See Figure 3. Install the Motor using four 5/16" carriage bolts (1002-2373) and four lock nuts (1001-1735).
Tighten bolts securely. NOTE: The motor pulley will be tightened in Step 13.
13. See Figure 4. Adjust the Belt Tensioner so the third mark on the tensioner is in line with the center of the
vertical post.
14. Align the Pulleys using a straight edge as shown in Figure 5. After the pulleys are aligned, install belt (1022-
3107) onto motor pulley, tension pulley, and prop pulley. Tighten down lock screws on the Pillow Bearings.
Recommended torque of the lock screws on the Pillow Bearings are 65 in.-lbs. min, and 83 in.-lbs. max.
15. Carefully lift fan into wall.
16. Securely attach fan to wall with screws (1004-1386).
Figure 5: Install Tensioner
Align third mark
with center of
post.
CAUTION!
Fan Is Heavy!
Do Not Attempt To Lift Fan Without Sufficient Workers And Equipment.

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 12 of 24
5. Assemble Cone
The cones are assembled as described in Section 5.1. The Packing List for each size and Tools
required for assembly are detailed below.
WARNING!
During Cone Installation Be Sure That Fan Motor Is Not Plugged Into Any Power Source.
Always Double Check Power Sources.
!
Tools Required
7/16 in. (11 mm) Wrench
Ratchet
½”socket
Cordless drill
9/16 in. (14 mm) Wrench
9/16 in. (14 mm) Socket
7/16 in. (11 mm) Socket
Philips (PH-3) Screw Driver
Marker or Scribe
3/8”, 5/16”, 7/16” Nut Driver
Rubber Mallet
Packing List for One(1) Cone/Damper Kit
54” Cone
52” Cone
48” Cone
36” Cone
Description
Quantity
--------------
0404-8253
0404-10332
0404-10048
Cone Sections
4
6403-3156
6403-3150
6403-2703
6403-3165
Damper Ring Assy.
1
--------------
1004-1424
1004-1424
1004-1424
3/8"-16 x 1-1/4” Cap Screws
4
--------------
1001-1457
1001-1457
1001-1457
3/8"-16 Nuts
4
--------------
1003-6027
1003-6027
1003-6027
3/8" Washers
8
6403-3050
6403-0147
6403-0156
6403-0135
PVC Coated Cone Guard
1
0006-5029
0006-5029
0006-5029
0006-5029
PL, Sheet Metal Plug 3/8 ID
2
1001-1446
1001-1446
1001-1446
1001-1446
1/4-20 Lock Nuts
16
--------------
--------------
1004-0117
--------------
1/4-20x2-1/2 Cap Screws
4
--------------
--------------
1003-0108
--------------
1/4”IDx5/8”OD Washer
4
--------------
--------------
1003-0112
--------------
1/4”IDx1”OD Washer
8
--------------
--------------
1403-10755
--------------
Spacer
4
6403-3174
6403-3162
6403-0096
6403-3167
Inlet Assembly
1
0404-10803
6403-7606
0404-10646
0404-10290
Damper Bumper Rod
1
1004-6013
1004-6013
1004-6013
1004-6013
1/4-20 x 3/4 Truss HD PH
4
0404-10652
0404-8252
0404-10516
0404-10291
Cone Bracket
4
1024-0108
--------------
1024-0105
1024-0105
Damper Bumper Spring
1
0404-11450
--------------
--------------
--------------
Cone Sections - Side
2
0404-11451
--------------
--------------
--------------
Cone Sections –Top/Bottom
2
1004-1401
1004-1401
1004-1401
1004-1401
1/4-20 x ½” Cap Screws
8
1004-1403
1004-1403
1004-1403
1004-1403
1/4-20 x 1-1/4” Cap Screws
4
1002-6068
1002-6068
1002-6068
1002-6068
5/16-18 x 5/8” Carriage Bolt
8
--------------
1001-0103
1001-0103
1001-0103
5/16-18 Lock Nuts
8
1001-0103
--------------
--------------
--------------
5/16-18 Lock Nuts
16
1003-6025
--------------
--------------
--------------
5/16" Washers
16
1004-1414
--------------
--------------
--------------
5/16-18 x 1” Cap Screws
8
1003-1461
--------------
--------------
--------------
1/4 USS Zinc Flat Washer
8
1004-1402
--------------
--------------
--------------
¼-20 x ¾” Cap Screws
2

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 13 of 24
5.1 Tab Cone Assembly
Cone Assembly Steps
a. Stand cone panels on edge with large end to ground as shown in Figure 10.
b. Slip four (4) cone panels together using tab and slot connections on edges of each panel.
IMPORTANT: All tabs must be on the inside of the cone assembly. The pilot holes and etched marks (orientation
indicators) must be located at the top and outside of the cone.
c. Place bolts through holes and thread nuts into place to hold four (4) cone panels together. Nuts must be located
on the outside of the cone assembly. Do not tighten nuts. Refer to Figures 9 & 11.
d. Once four (4) cone panels are assembled stand assembly up on large radius side. Refer to Figure 8.
e. Pull both ends together creating a heart shape as shown in Figure 10.
f. Place remaining bolts through holes and thread remaining nuts into place to hold cone together.
Nuts must be located on the outside of the cone assembly. Do not tighten nuts. Nuts to be tightened after cone
mounted on fan. Refer to Figure 11.
Figure 8: Fan Cone Panels
Figure 9: Cone Orientation Indicators
Slits for Collapsible
Side Panel 54” Cone
Only
IMPORTANT
All pilot holes and
etched numbers
must be located at
top & outside of
cone
Nuts on the
Outside

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 14 of 24
Nuts on outside of
cone assembly
Figure 10
Figure 9

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6. Attach Cone
a. Install the cone mounting brackets to the fan housing using two 5/16-18 x 1/2” carriage bolts in each mounting
bracket.
NOTE: Make sure bottom panel with drain hole is closest to the ground.
b. Bend the mounting brackets back slightly to help clear the area of the cone edges. Mount cone to fan. Hang the
centered slot in the small end of the cone over the Pim screw mounted on the Fan housing. See Figure 12.
Screw can be fastened with 1/4"-20 lock nut if necessary (not included).
c. Slide the cone over the outside of the orifice throat. Using four 1/4-20 x ¾” Truss Head Philips Screws and ¼-
20 lock nuts, insert the bolts from the inside of the cone through the mounting brackets. See Figure 13.
d. Tighten ¼-20 cone assembly nuts and bolts.
Cone Mounting
Brackets
Cone attaches to the
Cone Support Bracket
over the pim screw.
Figure 11:
Install Cone
Mounting Brackets
Figure 12
Top and Bottom cone
bracket bolts are inserted
from inside the cone.
NOTE for MF-36ED Cone:
Put bolts through second
hole of cone mounting
brackets.

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 16 of 24
7. Attach the Damper
1. Install the Damper assembly into cone. The springs that assist the Damper Doors to close are
oriented to the bottom.
2. Tighten all cone and Damper hardware.
3. The Damper Ring must be mounted in the holes closest to the orifice on the top, and farthest away from the
orifice in the bottom. The ring is to be tight. May require ring be tapped into place. Use 1/4-20 x 1.5" Hex
Head bolts, lock nuts and washers (provided) to attach ring to cone. Washers go on outside of cone. See
Figures 14 and 15.
NOTE:
Check the ring mounting from the side of the
fan. The ring is slanted to allow the force of
gravity to assist in closing the damper doors.
Figure 14:
Side View of Cone
Slanting the ring allows gravity to
assists the doors to shut.
Damper Door Springs are to be
located at the bottom of the cone.
CAUTION:
Fan Ring must be
plumb and level in
order for doors to
operate properly.
NOTE:
Fan Not Shown For
Clarity.
Upper cone ring fits
into inner hole.
NOTE:
Inner hole
will be
capped in a
later step.
NOTE: Lower cone ring
fits into outer hole.
Figure 13:
Damper Installation

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 17 of 24
NOTE for the 48"
Fan Guard ONLY:
Attach with spacer.
NOTE for 52” Fans
ONLY:
The top portion of
the Bumper Rod
Door Stop fits into
the same mounting
hole as top fan
guard eyelet.
Figure 18:
Install Fan Guard and Door Stop
Fan Guard
Bumper Rod
Figure 20:
Fan Guard Attachment for 54" Fan Cone
Bolt
Guard
Cone
Nut
Washer
Washer
Outside
Inside
8. Attach the Outside Fan Guard
8.1 36”, 48”, 52” and 54” Fan PVC-Coated Guard Assembly
For the 36” and 52” Fans, install the Outside Fan Guard using four 3/8-16 x 1-1/4” bolts and nuts and washers. See
Figure 18. See Figure 19 below for the 48” Fan Guard assembly which must use a longer bolt with spacer.
8.2 54” Fan Guard Assembly
For the 54” Fans, install the Outside Fan Guard using 5/16-18 x 1” bolts and nuts. See Figure 20.
NOTES: Use eight bolts for collapsed cone version OR six for the uncollapsed cone version.
Guard must be cut to fit when collapsing the cone.
Figure 19:
48” Outside Guard Assembly
1001-1446
1/4-20 nut
1003-0108
1/4"ID x 5/8"OD washer
0403-10755
spacer
1004-0117
1/4-20 x 2.5” bolt
1003-0112
1/4"IDx1"OD
Washers (2)

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 18 of 24
Figure 16 –Door Stop for 52" Fan
52” ONLY
3/8-16 x 1-1/4” Bolt
Fan Guard
3/8-16 x 1-1/4” Bolt
3/8-16 Nut
3/8 Washers
Bumper
Rod
3/8 Washers
3/8-16 Nut
Orifice-End
(Fan not
shown for
clarity.)
9. Attach the Door Stop Assembly
9.1 36”, 48”, 52”, and 54” Bumper Rod Door Stop Assembly
Install the Bumper Rod as shown by attaching the hooked end of the Bumper Rod into the tab at the
bottom of the Fan. Attach the Bumper Rod Spring to the top of the Bumper Rod and fasten the
spring to the top ring of the Fan Guard. See Figure 15.
36”, 48”, & 54”
ONLY
36”, 48”, & 54”
ONLY
Fan Guard
Bumper Rod
Spring
Hooked end of
Bumper Rod
Figure 15: Install Bumper Rod
Bumper Rod

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 19 of 24
Figure 22:
Assemble the Frame and Wire Guard
10. Inside Wire Guard
10.1 Wire Guard Cut-Out for Motor
1. Verify the power rating (Hp and Phase) and size of the drive motor which will be used in the Fan. A clearance
hole must be cut in the wire guard to tightly fit around the specific motor. The cut-out location, height, and
width will vary depending on the fan size and motor power ratings. Refer to Figure 21.
10.2 Wire Guard Installation
2. Assemble the Inlet Frame using 12 rivets (1005-1464). Refer to Figure 22. Place the Screen Guard into the
opening and bend the 12 tabs over the screen wire. Refer to Detail A.
Figure 21
Hole in Guard for Specific Motor
# of
Sections
# of
Sections
# of
Sections
# of
Sections
IMPORTANT!
Cut hole in screen to
tightly fit around the
specific fan motor.
Inlet Top
Inlet Side
Rivet
(1005-1464)
Screen Guard
Bend tab over
Screen Guard.
(See Detail A)
Inlet Side
2
Inlet frame
Tab
Insert Screen
Bend Tab
around
screen.
1
3
Detail A

4801-5327 Rev 1-15 Mega-Flow External Damper Fan - Unassembled Page 20 of 24
3. Install the Fan Inlet Frame with Wire
Guard by lifting the bottom into the slot
at the bottom of the fan housing. The
Wire Guard has a cut opening hole for
the motor. Use two spring latches on
either side of the fan housing to secure
the Inlet Frame. See Figure 23.
4. There are two unused holes in the bottom of the
cone. For reference, refer back to Figure 13. Place
plastic plug in these holes to prevent light from
passing through. See Figure 24.
5. There are two pre cut drain holes in the
bottom of the fan housing in either corner
and one in the bottom center of the cone.
These may be opened if necessary. See
Figure 24.
6. Affix labels to fan as shown in Figure 25.
7. Connect power to fan and verify proper operation.
8. Fan, Cone, and External Damper installation complete.
Figure 23: Install Fan Inlet Frame
Wire Guard
opening for
motor
Figure 24: Fill Unused Holes in Cone
Fill unused
holes in
cone
Water
Drain
Holes
Figure 25: Affix Labels
Warning Hand
(4501-1116)
Danger Hand
(4501-2622)
Made in USA
(4501-2957)
Danger Head
(4501-2620)
INSIDE
MEGAFLOW
(4501-6084)
OUTSIDE
BOTTOM INSIDE
Bearing
Maintenance
(4501-6128)
Rotary
Tensioner
(4501-6129)