Accurex XRUD, Manual

Page: 46 / 64

ROOF EXHAUST TYPICAL INSTALLATION XRED AND XREB
FAN INLET CONNECTIONS
WHEEL ROTATION
Disconnect
Recommended Duct
and Damper Size
Damper
8 or 12 in.
(203 or 305)
1¼ in.
(32)
Recommended Roof
Opening
*Dimensions shown
in inches (mm)
1¼ in.
(32)
Wiring by Others
¾ in.
(19)
Good
Good Poor Poor
Good
Good Poor Poor
Good
Good Poor Poor Good
Good Poor Poor
Clockwise Rotation
Counterclockwise
Airflow
Clockwise Rotation
Counterclockwise
Airflow
Models XREB and XRED exhaust fans are designed to
meet the needs of general clean air applications. Tests
were conducted to ensure safe, rugged and reliable fans.
Due to the varying airstreams encountered in commercial
ventilation, system designers must be aware of national,
state, and local codes and guidelines governing these
installations. Local code authorities should be consulted
before proceeding with any ventilation project.
Roof curbs should be 11/2 inches (3/4 inch on a side)
less than the unit curb cap to allow for roofing
and flashing.
Installation must include a means for inspecting,
cleaning and servicing the exhaust fan.
Dampers must open fully.
Use motorized dampers
in low airflow applications
to reduce losses. Avoid sharp turns or
entrance conditions,
which cause uneven
flow. Use turning vanes
in elbows to reduce
adverse effects. Provide uniform airflow
at fan inlet to ensure
optimum performance. Provide uniform airflow
at fan inlet and through
the damper to ensure
optimum performance.
The curb cap should be
three wheel diameters
from the radius. Use
turning vanes in duct
when possible.
Direction of rotation is very critical. Rotation in the wrong direction
will result in excessive horsepower, possible motor burnout and
increased noise levels. Check rotation by energizing the unit only
momentarily. The rotation should be clockwise when viewed from the
top of the unit and the same as the rotation decals affixed to the unit.
Clockwise Rotation Counterclockwise Airflow