Roof Mounted Unit - Arrangement Dbc - Greenheck DG Installation, Operation And Maintenance Manual

Installation of Roof Mounted Unit
Arrangement DBC
1. Install Curb/Equipment Support(s)
Position curb/equipment support(s) on the roof
(reference the CAPS submittal for placement of curb/
equipment support(s) in relation to the unit). Verify that
all unit supports are level, shim if necessary. Attach
curb to roof and flash into place. Attach the equipment
support(s) to the roof, remove metal cover, flash to
wooden nailer and reinstall cover.
Metal Cover
Equipment
Support
Curb and Equipment Support
2. Install Combination Curb Adaptor
Install combination curb adaptor over curb, use wood
screws to lag in place. Locate extension so the tall
louvered side is over the exhaust opening, as shown
in illustration. Caulk extension to combination curb
adaptor. Fasten extension to curb adaptor with #12
sheet metal screws (field-provided).
Combination Extension
3. Install Ductwork
Good duct practices should be followed for all
ductwork. All ductwork should be installed in
accordance with SMACNA and AMCA guidelines,
NFPA 96 and any local codes. Reference the CAPS
submittal for ductwork size and location.
Ductwork
®
Roof Curb
Exhaust
1 inch
Inside Flange
Supply
Exhaust
Ductwork
by Others
Supply
Ductwork
by Others
NOTE
The use of a duct adapter is recommended on a
downblast (DBC) arrangement to align the ductwork
with the supply unit. The duct adapter is only a guide
and is not to be used as a support for the ductwork.
4. Apply Sealant
Apply an appropriate sealant around the perimeter of
the curb and duct adapter(s) to isolate fan vibration and
prevent water penetration.
Sealant
Supply Duct with
Duct Adapter Installed
Sealing Ductwork
5. Install Exhaust Fan
Fasten exhaust fan to curb extension with self-tapping
sheet metal screws. Installing the exhaust fan prior
to the supply unit will allow for easier installation of
options.
Installing Exhaust Fan
NOTE
NFPA 96 requires the exhaust fan to be hinged.
6. Install Exhaust Options
Install optional hinge kit with restraining cables and
grease trap with drain connection.
Direct Spark Ignition Make-Up Air
Exhaust Duct Installed
Exhaust Fan
5