Form I-XE/CRGB/RPB, Page 10
*Optional
Downturn Plenum
Furnace
Blower
Cabinet
Curb
Cap
1-7/8
(48mm)
Roof
Curb
16 (406mm)
1-7/8
(48mm)
AC
D
Return
Duct
Supply
Duct
1-7/8(48mm)
1-1/2
(38mm)
Lift Holes
(4 corners)
B
**
C
and
D
are roof opening
dimensions.
***
Field installed means that the cooling coil cabinet with or without the downturn is factory assembled
and shipped separately. The roof curb is sized to accommodate the complete length of the system. The
shipped-separate cooling coil cabinet with or without a downturn must be lifted to the roof separately
from the packaged system, set on the roof curb, and attached to the furnace section (see instructions
beginning on page 38).
16
(406mm)
1-7/8(48mm)
4
(102mm)
2 x 6 Wood Nailer
1-1/2 x 3 lb
Fiberglass
Flashed by the
installer (flashing must
be under lip of curb)
Lag Screw
Cap
Screws
For top 4 holes (2 on
each side) at both joints,
from
inside
the curb insert
(4) 5/16 x 1 lag screws
and (4) 5/16 lockwashers.
For bottom 4 holes (2 on each side) at both
joints, from
outside
of the curb insert (4)
5/16-18 x 3/4 long cap screws. Attach with
5/16 lockwashers and 5/16-18 hex nuts.
(Inside
of Curb)
7B. Mounting Outdoor Models on a Roof Curb (cont'd)
Curb Cap
Counter Flashing
(by installer)
Cant Strip
(by installer)
MUST be sealed
between curb cap
and roof curb
2 x 6
Wood
Nailer
Insulation
16
(406 mm)
Curb Height
Cabinet
Curb Cap Skirt
Weld, bolt, or lag screw curb to deck structure.
Roof Curb
Roofing Felts
(by others)
IMPORTANT:
Top surface of curb
MUST
be sealed. See instructions above.
*
Illustration is shown with an Option AQ5 or AQ8 downturn plenum. The system can have a
variety of configurations which affect installation.
• If the system does not have a downturn plenum, the discharge is horizontal.
• Downturn plenum
Options AQ5 and AQ8 are factory installed to be lifted to the roof
and set on the roof curb as part of the packaged system.
• If the system has an Option AU2 or AU3 cooling coil cabinet, the discharge is horizontal. If
the system has an AU11, AU12, AU13, AU14 cooling coil cabinet, there is a downturn
plenum with vertical discharge.
Options AU2, AU3, AU11, AU12, AU13, and AU14 are
not factory installed. Options AU2, AU3, AU11, AU12, AU13, and AU14 must be
lifted to the roof separately from the packaged system, set on the roof curb, and
attached to the furnace.
FIGURE 8 -
Optional Roof Curb
Splicing
Detail
Corner Detail
Curb Section
Typical
Curb
Detail
IMPORTANT:
Area enclosed
by the roof curb must comply with
clearance to combustible materials.
If roof is constructed of combustible
materials, area within curb must be either ventilated, left open, or covered
with non-combustible material which has an "R" value of at least 5.0. If
area within curb is left open, higher radiated sound levels may result.
Roof Curb Dimensions (inches)
S ize
75, 100,
125
150, 175
200, 225
250, 300
350
400
S ize
75, 100,
125
150, 175
200, 225
250, 300
350
400
A
60-5/8
60-5/8
60-5/8
60-5/8
60-5/8
60-5/8
A
98-3/8
103-7/8
109-3/8 117-21/32 123-5/32 128-21/32
B
24-5/16
29-13/16
35-5/16
43-9/16
49-1/16
54-1/2
B
24-5/16
29-13/16
35-5/16
43-9/16
49-1/16
54-1/2
C
**
56-15/16 56-15/16 56-15/16 56-15/16
56-15/16
56-15/16
C
**
94-5/8
100-1/8
105-5/8 113-29/32 119-13/32 124-29/32
D
**
20-9/16
26-1/16
31-9/16
39-13/16
45-5/16
50-13/16
D
**
20-9/16
26-1/16
31-9/16
39-13/16
45-5/16
50-13/16
A
84-9/16
84-9/16
84-9/16
84-9/16
84-9/16
84-9/16
A
122-3/8
127-7/8
133-3/8 141-21/32 147-5/32 152-21/32
B
24-5/16
29-13/16
35-5/16
43-9/16
49-1/16
54-1/2
B
24-5/16
29-13/16
35-5/16
43-9/16
49-1/16
54-1/2
C
**
80-13/16 80-13/16 80-13/16 80-13/16
80-13/16
80-13/16
C
**
118-5/8
124-1/8
129-5/8 137-29/32 143-13/32 148-29/32
D
**
20-9/16
26-1/16
31-9/16
39-13/16
45-5/16
50-13/16
D
**
20-9/16
26-1/16
31-9/16
39-13/16
45-5/16
50-13/16
Option CJ4 - Roof Curb for (H)CRGB and (H)RPB with Field-
Installed*** Cooling Coil Cabinet Option AU2 or AU3
Option CJ5 - Roof Curb for (H)CRGB and (H)RPB with Field-
Installed*** Cooling Cabinet and Downturn Plenum Option AU11,
AU12, AU13, or AU14
Option CJ2 - Roof Curb for (H)CRGB and (H)RPB with Factory-
Installed Downturn Plenum Option AQ5 or AQ8
Option CJ1 - Roof Curb for (H)CRGB and (H)RPB
