
®
ASSEMBLY INSTRUCTIONS
STEP 1: Unpack and Inspect Parts
PART # 457157
Roof Curb and Duct Adapter
Model: ERT
Part Description Qty
Roof Curb Kit 12 in. high 1 851518 851646 851646 851516
16 in. high 1 851519 851647 851647 851517
1. End Channel 12 in. high 2 657226 659321 659321 657209
16. in. high 2 657332 659336 659336 657216
2. Side Channel 12 in. high 4 657227 659322 659322 657210
16 in. high 4 657333 659337 659337 657217
3. Supply Side Channel 12 in. high 2 — — — 657211
16 in. high 2 — — — 657218
4. Center Channel 12 in. & 16 in. high 1 657228 659328 659328 657212
Part Description Qty
Duct Adapter (12 in. & 16 in. high curbs)
5. Curb Cross Channel 1 657228 2 659328 2 659328 2 657212
6. Duct Side Channel 3 657229 3 659329 3 659329 4 657213
ERT-52 ERT-58 ERT-64 ERT-74
P/N P/N P/N P/N
ERT-52
P/N P/N P/N P/N
Qty
ERT-58
Qty
ERT-64
Qty
ERT-74
7. Duct Cross Channel 1 657230 2 659330 2 659330 2 657214
Hardware Kit (for curb & duct adapter) 1 851525 1 851523 1 851523 1 851523
3/8-16 x 3/4 Serrated Flange Bolts 24 415459 32 415459 32 415459 32 415459
3/8-16 x 3/4 Serrated Flange Nuts 24 415457 32 415457 32 415457 —
Screws, SMS (A) 12 x 0.625 (IHH) 20 415180 32 415180 32 415180 —
Note: Hardware kit for the 12 in. high and 16 in. high roof curb are the same.
Tools Recommended for Assembly
• Cordless drill
• 5/16 in. Nut setter
• 9/16 in. Nut setter
• Open or Closed 9/16 in. wrench
• Awl — for hole alignment
November 2006

STEP 2: Assemble Main Curb
Hardware Required: (24 or 32) 3/8-16 x 3/4 Serrated Flange Bolts
(24 or 32) 3/8-16 x 3/4 Serrated Flange Nuts
(4) Side Channels
(2) End Channels
(1) Center Channel
(2) Supply Side Channels (for ERT-74 only)
Instructions: • See Main Curb Assembly for positioning the Side, Center, and End Channels.
• Align the holes and fasten as shown below.
Channel Lengths and Overall Curb Dimensions
Side
Length
ERT-52
ERT-58
ERT-64
ERT-74
All dimensions shown in inches.
75.25 65.50 65.50 154.50 65.50
88.00 74.75 74.75 180.00 74.75
88.00 74.75 74.75 180.00 74.75
4 @ 59.75
2 @ 71.25
End
Length
92.75 92.75 195.00 92.75
Center
Length
LW
ERT-74
ERT-52 and ERT-58/64
L
W
L
W
End
Side and center channels
fasten together, as shown.
2
End and side channels
fasten together, as shown.
®

IMPORTANT! The following steps are for ductwork support. These steps are required only
if the ductwork will be installed prior to the ERT unit.
STEP 3: Fastening Curb End Support and Curb Center Support Channel
(Items 4 & 5)
Hardware Required: (8) Screws, SMS (A) 12 x 0.625 (IHH)
(1 or 2) Curb Cross Channel
Instructions: • Position the Curb Cross Channel
• Align the holes and fasten using (4) 12 x 0.625 (IHH) screws.
ERT-52
ERT-74
ERT-58 &
ERT-64
3
® ®

STEP 4: Fastening Duct Cross and Side Channel(s) to Curb Cross
Channels and Main Curb Assembly
Hardware Required: Screws, SMS (A) 12 x 0.625 (IHH)
Quantity: ERT-52
(16) of the above screws are needed to attach the Duct Cross and Side Channels to
the Curb Cross Channel and Main Curb Assembly
ERT-58/64 and ERT-74
(24) of the above screws are needed to attach the Duct Cross and Side Channels to
the (2) Curb Cross Channels
Instructions: • Position the Duct Cross and Side Channels (shown in gray) as depicted
• Align the holes and fasten using the above hardware.
ERT-58 &
ERT-64
ERT-52
ERT-74
4

STEP 5: Final Roof Curb Assembly
STEP 5: Final Roof Curb Assembly
ERT-58 &
ERT-64
ERT-52
Duct Adapter Assembly
Duct Adapter Assembly
Exhaust
Inlet
Supply
Discharge
2
2
1
4
1
5
6
7
Exhaust
Inlet
Supply
Discharge
2
2
1
4
1
5
6
7
5
®

STEP 5: Final Roof Curb Assembly
1
2
4
Exhaust
Inlet
Supply
Discharge
2
ERT-74
6
6
1
Duct Adapter Assembly
7
5
#457157 IOM ERT Curb
Rev. 3, November 2006
Copyright © 2006 Greenheck Fan Corp.