Sterling RT - Manual (Page 13)

(U) RC011, (U)RC012
To avoid any property damage or
personal injury, it is the installers responsibility
to make sure that the installation will not impair
the function of this curb, or the unit to be
installed.
All curbs must be mounted on level areas. The roof must
be suitable to support the weight of both the curb and
the unit to be mounted. The enclosed area of the roof
curb must comply to required clearances to combustible
materials. If the roof construction is made of combustible
materials, the enclosed roof curb area must meet the
following requirements:
1. Ventilate this area.
2. Leave area open (however, this may elevate higher
sound levels.)
3. Cover this area with non-combustible material,
which utilizes an “R” value of 5.0 minimum.
Position and assemble the curb, referring to Figures 17
thru 23, 33 and 34 Use the following procedure:
1. All hardware used for these assembly procedures is
included with your curb, and should be used. Do not
tighten any hardware until the curb is completely
level and square, and installed in a suitable position
on the roof, with proper alignment to the roof/unit
opening(s).
2. Position and install the end and side curb rail sub-
assemblies, aligning around the roof opening loca-
tion(s).
3. Position and install the inner cross brace(s) and
ductwork brackets as shown.
4. Secure the roof curb to the roof decking.
5. Install the field supplied flashing/materials.
6. Apply the gasketing (included with the kit) on the top
flanges/surfaces on the curb as shown
To avoid any property damage or
personal injury, it is the installer’s responsibility
that the roof curb and unit must be completely
sealed, preventing any water or air leakage/
damage.
Figure 18 - Roof Opening Specifications
Unit Type [ UT ] “AH”
* 20-7/8"
(530)
E
*
Return
Air
Opening
Section
Y-Y
Section
X-X
Capacity
[ CA ]
Dimension
E *
20
40
37"
(940)
53-1/2"
(1359)
* All Dimensions Shown Have Been Calculated To
Include A One (1) Inch Clearance Around Return
Duct.
CURB SPECIFICATIONS
* ROOF OPENINGS
D3809-5A
Dimensions are in inches (Dimensions in parenthesis are in millimeters).
Refer to Figure 20 for Section X-X and Y-Y details.
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