Installation Sheet

TRUEZONE ARD, EARD, AND ZD SERIES DAMPERS
3 33-00040—03
Installing the Round (ARD and
EARD) Dampers
1. Insert the crimped end of the ARD or EARD into the
uncrimped end of the rigid round duct and secure
with sheet metal screws (not provided). When using
flexible duct, slip the duct over the end of the ARD or
EARD and secure it with duct straps (not provided).
2. When installing the damper in a horizontal
application, make sure the motor actuator is located
on the side or top of the damper. Do not locate the
motor on the bottom of the damper. The damper can
be mounted in a vertical duct.
3. Adjust Range stop position to desired closed
positions. ARD and ZD Dampers are completely
closed in position 0. EARD Dampers are completely
open in position 0.
Fig. 2. TrueZONE Actuator range stop positions.
Wiring Multiple Dampers
When the same zone controls two or more dampers, wire
the dampers in parallel to terminals M1 and M6 on the
zone control panel.
INSTALLATION OF ZD
DAMPER
When Installing this Product…
1. Read these instructions carefully. Failure to follow
these instructions can damage the product or cause
a hazardous condition.
2. Check the ratings given in the instructions and on
the product to make sure the product is suitable for
your application.
3. Installer must be a trained, experienced service
technician.
4. All wiring must comply with local electrical codes,
ordinances, and regulations.
5. After completing installation, use these instructions
to check out the product operation.
Planning the Installation
Selecting a Location
Select a location for the zone dampers that is at least three
feet from the HVAC unit plenum in the air duct takeoff to
the respective zone and is easily accessible for checkout
and maintenance.
The ZD comes complete and ready for installation. The
motor and linkage are factory-assembled to the damper.
The damper is assembled for installation and wiring to the
control panel.
Selecting Damper Size
To ensure correct operation, be sure to select the correct
zone damper size for the air duct:
IMPORTANT
Be aware that ZD damper sizes are built 5/32 in.
smaller than the listed dimensional sizes.
• If the damper is forced into an undersized air duct, the
excess pressure can jam the damper blades and cause
improper operation.
• When a small percentage of continuous flow is desired
in a zone, even when the damper blades are closed,
adjust motor closed position to be slightly open to
maintain desired air flow.
Selecting Location with Humidifier
Installed
IMPORTANT
Excessive lime or mineral deposits can
accumulate on damper blades and cause
improper operation when spray or atomizing type
humidifiers are installed in the furnace plenum or
air supply duct with the zone dampers.
• Spray or atomizer type humidifiers that are installed in
the furnace plenum or air supply duct are not
recommended.
• Evaporative type humidifiers are recommended.
Installing the Damper
IMPORTANT
— Install dampers into a squared air duct.
— Do not weld dampers to the air ducts.
— Do not force dampers into undersized air ducts.
Excess pressure can damage damper blades.
— Be sure high limit setting is less than 200 °F
(93 °C).
— Higher settings can damage the electric actuator.
1. Be sure the ZD is correctly sized to the air duct (see
Selecting Damper Size section).
2. Select a ZD location that is three feet from the
furnace plenum.
3. Cut a 4-in. (102 mm) opening in the accessible side
of the air duct at the location selected; ensure the
opening of the air duct is cut fully from seam to
seam.
4. Secure the ZD mounting plate to the air duct with the
self-tapping sheet metal screws provided.
M35187A
RANGE STOP
LOCATIONS