Roof curb mounting – Greenheck Fan HEAT RECOVERY UNIT WITH EVAPORATIVE COOLING HRE-20 User Manual
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Rooftop units require curbs to be mounted first . The duct connections must be located so they will be clear of
structural members of the building .
1. Factory Supplied Roof Curbs
Roof curbs are Model GKD, which are shipped in a
knockdown kit (includes duct adapter) and require field
assembly (by others) . Assembly instructions are included
with the curb .
2. Install Curb
Locate curb over roof opening and fasten in place . (Refer
to Recommended Roof Openings) . Check that the diagonal
dimensions are within ±1/8 inch of each other and adjust as
necessary . For proper coil drainage and unit operation, it is
important that the installation be level . Shim as required to
level .
3. Install Ductwork
Installation of all ducts should be done in accordance with
SMACNA and AMCA guidelines. Duct adapter provided to
support ducts prior to setting the unit .
4. Set the Unit
Lift unit to a point directly above the curb and duct
openings . Guide unit while lowering to align with duct
openings . Roof curbs fit inside the unit base . Make sure the
unit is properly seated on the curb and is level .
L
W
All dimensions shown are in inches .
Curb Outside Dimensions
Roof curb details, including duct location
dimensions, are available on HRE roof curb
assembly instructions.
ROOF CURB
SIDE OF UNIT
BASE
1 INCH INSULATION
E
D
C
A
B
Curb Outside Dimensions
Weight
Model
L
W
HRE-20
93
51
280
HRE-45
100 .5
60 .63
355
HRE-55
112 .75
71 .5
450
HRE-90
125 .75
90 .75
625
Model
Curb Cap Dimensions
A
B
C
D
E
HRE-20
2 .00
2 .00
1 .00
0 .88
0 .75
HRE-45
2 .00
4 .25
2 .00
1 .31
0 .50
HRE-55
2 .00
4 .25
2 .00
1 .31
0 .50
HRE-90
2 .00
4 .25
2 .00
1 .31
0 .50
All dimensions shown are in inches .
Curb CAP Details for Factory Supplied Roof Curbs
ROOF CURB MOUNTING