Auto-Zone Control Systems Auto-Zone Plus Systems Installation & Operation (Version 03A) - Manual (Page 48)

Section 2
Auto-Zone Plus
2-16 Design Guide
Bypass Dampers
The Bypass Damper can be either round or rectangular. The Round Bypass Damper is
supplied with the Damper Actuator and Bypass Wiring Interface Board factory mounted
in a sheet metal enclosure attached to a Round Air Damper assembly. This Round Bypass
Damper Package is field connected to the appropriate size round duct. Rectangular
Bypass Dampers mount directly in the rectangular ductwork using flanged connections
field formed in the rectangular ductwork. A Rectangular Bypass Damper Kit is required
to complete the Rectangular Bypass Damper package. The Rectangular Bypass Damper
Figure 2-10:
Round And Rectangular Bypass Dampers
Kit is supplied with the Damper Actuator and Bypass Wiring Interface Board factory
mounted in a sheet metal enclosure. This assembly is then field mounted over the
Rectangular Damper shaft and secured to the ductwork with sheet metal screws.
Up to two additional Rectangular Bypass or Round Bypass Dampers can be slaved
together when it is not practical to use a single large damper. See Figure 2-11. The
bypass damper(s) should be installed as close as possible to the rooftop unit.
Round and Rectangular Bypass Dampers should be securely hung using either wire
cradles or metal strapping. While the dampers may be hung in any position, avoid sharp
kinks in flexible duct to prevent airflow restrictions. The Round Bypass Dampers are
insulated for use in non-conditioned spaces to avoid sweating and to improve energy
efficiency.