Twin City IM-4720NFS User Manual

A

MGR, MGI Modular Gravity Hood

(throat sizes 72" & smaller)

INSTALLATION & ASSEMBLY MANUAL

See Catalog 4720 for sizes that ship assembled.

IM-4720NFS

August 2013

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24 Cap Screw, Serrated Flange, 1/4-20 x 5/8"
24 Hex Nut, Serrated Flange, 1/4-20

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4 Doubler plates
4 Cap Screw, Serrated Flange, 5/16-18 x 3/4"
4 Hex Nut, Serrated Flange, 5/16-18

Note: Not always required.

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16 Nut Clip - 1/4-20
24 Cap Screw, Serrated Flange, 1/4-20 x 1"

8 Hex Nut, 1/4-20

Hardware Kit #1A

Item

Hardware Kit #1C

Item

Hardware Kit #2

Item

Figure 1.

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8 Cap Screw, Serrated Flange, 5/16-18 x 3/4"
8 Hex Nut, Serrated Flange, 5/16-18

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40 Screws, #12 x 3/8"

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A/R Hood Clips (Only for hood panels longer than 108")

Hardware Kit #3

Item

Hardware Kit #4A

Item

Hardware Kit #5

Item

Hood Panel

Hood End Panel
Assembly (Female Rib)

Hood End Panel

ssembly (Male Rib)

Hood Rail Assy

Birdscreen Assy
Fixed

Base Assy

Birdscreen Assy
Removable

Hood Support Angle

©2013 Twin City Fan Companies, Ltd.

Step 1 – Base Assembly

Curb Base Side

Figure 2.

Fasteners (Kit #1A and #1C) – Note: There may
be extra fasteners.

Lay out the Curb Base Side and Curb Base
End in approximate location to each other. See

Figure 2. Use (3) 1/4-20 fasteners for 5" base
height and (4) 1/4-20 fasteners for 12" base
height. Leave top two holes open on the Base
End. Note: Hand tighten only until Step 3. On
some hoods, a Doubler Plate is required. See
Detail A in Figure 2.

Curb Base End

Doubler Plate

DETAIL A

* When Kit 1C provided.

Screw

Hex Nut

Step 2 – Hood Mount Bars

Fasteners (Kit #1A and #1C)

Loosely assemble Hood Mount Bars on both sides of the Curb Base Ends using (4) 1/4-20 fasteners per side. On
hoods using a Doubler Plate, mount Brace using 5/16-18 hardware. See Figure 3b.

Figure 3a. Figure 3b.

Hood Mount Bar

Hood Mount Bar

Brace

Step 3 – Caulk

Caulk inside corners of base assembly and tighten all fasteners. Install assembly onto roof curb before proceeding.
Ensure that assembly is properly anchored to roof curb.

Step 4 – Birdscreen

Fasteners (Kit #2) – Note: There may be
extra fasteners.

Install nut clips onto Hood Mount Bars as
shown. Center Fixed Birdscreen on assem­bly with equal overhang on both sides.
Attach using (4) 1/4-20 x 3/4" fasteners
per birdscreen as shown.

Figure 4.

Screw

Nut Clip

Hood Mount Bar

Extension Tab

Fixed Birdscreen

Overhang

Overhang

2 Twin City IM-4720NFS

Step 4 – Birdscreen (Continued)

End Panel Assy,

Male

- This flange must

Removable

Install two Removable Birdscreens. After positioning the assemblies, rotate the locking tabs in place and tighten.

Figure 5.

Birdscreen

Locking Tab,

rotate into place

and tighten

Removable

Birdscreen

Detail of locking tabs

Step 5 – Hood Rails

Fasteners (Kit #3) – Note: There may be extra fasteners.

Install two Hood Rail Assemblies to the Hood Mount Bars using cap screws and nuts. Do not fully tighten fasteners.
They will be tightened in Step 8.

Figure 6.

Hood Rail Assembly

Base Assembly

Hex Nut,

Flanged Head

Screw,
Serrated Flange

Step 6 – Hood End Panel

Fasteners (Kit #4A and #5) – Note: There may be extra fasteners.

Install Male End Panel Assembly using #12 screws.

Figure 7.

End Panel Assembly

-Male-

Sheet metal Screw

IMPORTANT
male. Refer to Figure 8.

- This flange must be

Figure 8.

Male Flange

(Narrow)

End View of Panel

Female Flange

(Wide)

3 Twin City IM-4720NFS

Step 7 – Hood Panels

Female

Female

Fasteners (Kit #4A and #5)

Install Hood Panels using #12 screws. Place female end of next panel over male end of end panel. See Detail A.
On sizes where hood width is 108" and larger, hood clips must be installed at each interlocking rib while installing
the panels. Position the Hood Panel in place and reach underneath to slide the Hood Clip into place. See Detail B.

Figure 9.

Hood Panel

A

Hood

Width

Male

Male

NOTE: Use Hood Clips on Hood Panels 108" and wider.

DETAIL B

DETAIL A

Hood Clip

Step 8 – Hood End Panel

Fasteners (Kit #4A)

Install Female End Panel Assembly using #12 screws. Fully tighten the Hood Mount Bar/Side Rail fasteners from
Step 5.

Figure 10.

Step 9 – Screen Clips

Rotate Screen Clips on End Panel Assembly to support the bird screen.

Figure 11.

Screen Clip

End Panel Assembly

-Female-

#12 Screw

TWIN CITY FAN & BLOWER | WWW.TCF.COM

5959 Trenton Lane N | Minneapolis, MN 55442 | Phone: [phone] | Fax: [phone]

3MWG08/13