Roof Curb; Downflow; Rigging - Trane YHC092E Installation, Operation And Maintenance Manual

Roof Curb

Downflow

The roof curbs for these units consists of a "full perimeter"
enclosure to support the unit just inside of the unit base
rail. The 7 ½ - 10 ton high efficiency units contain a support
base alignment rail and will extend past the end of the roof
curb as shown in figures below.
Before installing any roof curb, verify;
• It is the correct curb for the unit,
• It includes the necessary gaskets and hardware,
• The installation location provides the required
clearance for proper operation,
• The curb is level and square. The top surface of the
curb must be true to assure an adequate curb-to-unit
seal.
WARNING
Combustible Materials!
Maintain proper clearance between the unit heat
exchanger, vent surfaces and combustible materials.
Refer to unit nameplate and installation instructions for
proper clearances. Improper clearances could result in
combustible materials catching on fire. Failure to
maintain proper clearances could result in death or
serious injury or property damage.
Verify that appropriate materials were used in the
construction of roof and ductwork. Combustible materials
should not be used in the construction of ductwork or roof
curb that is in close proximity to heater elements or any
hot surface. Any combustible material on the inside of the
unit base should be removed and replaced with
appropriate material.
Step-by-step curb assembly and installation instructions
ship with each accessory roof curb kit. Follow the
instructions carefully to assure proper fit-up when the unit
is set into place.
Note: To assure proper condensate flow during
operation, as well as proper operation of the
condensate overflow switch (if equipped), the unit
and curb must be level.
If the unit is elevated, a field constructed catwalk around
the unit is strongly recommended to provide easy access
for unit maintenance and service.
Recommendations for installing the Supply Air and Return
Air ductwork joining the roof curb are included in the curb
instruction booklet. Curb ductwork must be fabricated and
installed by the installing contractor before the unit is set
into place.
Note: For sound consideration, cut only the holes in the
roof deck for the ductwork penetrations. Do not cut
out the entire roof deck within the curb perimeter.
RT-SVX21K-EN
Figure 22. View for base to roof curb alignment
YHC092-120E (except YHC092F) on 50" x
84" roof curb
Base Alignment Bracket
Figure 23. View for base to roof curb alignment
YHC092-120E (except YHC092F) on 60" x 84"
roof curb
If a Curb Accessory Kit is not used:
• The ductwork can be attached directly to the factory-
provided flanges around the unit's supply and return
air openings. Be sure to use flexible duct connections
at the unit.
• For "built-up" curbs supplied by others, gaskets must
be installed around the curb perimeter flange and the
supply and return air opening flanges.

Rigging

WARNING
Heavy Objects!
Ensure that all the lifting equipment used is properly
rated for the weight of the unit being lifted. Each of the
cables (chains or slings), hooks, and shackles used to lift
the unit must be capable of supporting the entire
weight of the unit. Lifting cables (chains or slings) may
not be of the same length. Adjust as necessary for even
unit lift. Other lifting arrangements could cause
equipment or property damage. Failure to follow
instructions above or properly lift unit could result in
unit dropping and possibly crushing operator/
technician which could result in death or serious injury.
Installation
23