Auto-Zone Control Systems Auto-Zone Basic Systems Installation & Operation (Version 02C) - Manual (Page 40)

Section 2 Auto-Zone Basic
2-10 Installation and Wiring
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 By-
pass 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 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 Rec-
tangular Damper shaft and secured to the ductwork with sheet metal screws.
Figure 2-8: Round and Rectangular Bypass Dampers
Up to two additional Rectangular Bypass or Round Bypass Dampers can be slaved to-
gether when it is not practical to use a single large damper. See Figure 2-9. 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 cra-
dles 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 in-
sulated for use in non-conditioned spaces to avoid sweating and to improve energy effi-
ciency.
See Figure 2-2 for a typical bypass damper mounting location. See Figure 2-9 for typical
Bypass Wiring Interface Board wiring instructions.