Installing Equipment Interface Module (If Used); Wiring 24 Vac Common; Selecting Discharge And Return Air Temperature Sensor; Sensor Mounting Locations - Honeywell THX9321 Prestige 2.0 Product Data

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THX9321 PRESTIGE 2.0 AND THX9421 PRESTIGE
Installing Equipment Interface
Module (if used)
If no Equipment Interface Module is used, skip to "Selecting
Thermostat Location" beginning on page 12.
NOTE: If an EIM is mounted inside a metal cabinet, such
as a commercial rooftop unit, it is recommended
to use a THM4000R1000 Wireless Adapter for
extended wireless range. Mount the Wireless
Adapter outside the metal cabinet and connect to
the ABCD terminals at the EIM. The Wireless
Adapter functions as a remote antenna for the
EIM. After it is wired to the EIM, it automatically
takes over as the antenna for RedLINK communi-
cation. For best RedLINK performance, avoid
mounting the Wireless Adapter above the roof
deck or outside the exterior walls.
NOTE: If you install more than one thermostat and EIM,
the EIMs must be at least 2 feet apart for best
RedLINK performance.
WIRELESS
ADAPTER
THM4000R
POWER
WIRELESS SETUP
CONNECTED
CONNECT
CAUTION
Electrical Hazard.
Can cause electrical shock or equipment damage.
Disconnect power before wiring.
The Equipment Interface Module (EIM) can be mounted
vertically on the HVAC equipment or on a wall in the equipment
room.
68-0311—02
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EIM
A
B
C
D
Fig. 8.
IAQ WITH EIM
1. Mount the EIM near the HVAC equipment or on the
equipment itself. Use screws and anchors as appropriate
for the mounting surface..
2. To wire the EIM, strip 1/4" insulation, then insert wires
(see Fig. 9). For wiring diagrams, see "Wiring" beginning
on page 135.

Wiring 24 Vac Common

• Single-Transformer System—Connect the common side of
the transformer to the C screw terminal of the EIM. Leave
the metal jumper wires in place between R, RC, and RH.
• Two-Transformer System—Connect the common side of the
cooling transformer to the C screw terminal of the EIM.
Remove the metal jumper wire between RC and RH.
Connect the hot side of heating transformer to RH and leave
the jumper wire between R and RC and connect the hot
side of cooling transformer to R or RC.
Selecting Discharge and Return Air
Temperature Sensor Mounting
Locations
Refer to the guidelines below and Fig. 10–14 for mounting
locations of the Discharge and Return Air Temperature
Sensors.
Selecting Discharge Air Temperature
Sensor Mounting Location
1. Mount the Discharge Air Temperature Sensor on the
supply duct in a location where the air is mixed well.
Mount the Discharge Air Temperature Sensor out of sight
of the A-Coil/Heat Exchanger when possible. See Fig.
10.
2. When possible, mount the Discharge Air Temperature
Sensor upstream of a Steam Humidifier, a Fan Powered
Humidifier or a Dehumidifier that is ducted to the supply.
See Fig. 11–12.
3. If space does not allow a Discharge Air Temperature
Sensor upstream of a Steam Humidifier or Fan Powered
Humidifier, mount the Discharge Air Temperature Sensor
downstream of the Humidifier. See Fig. 11. When setting
the Delta T Limits (see "Set Delta T Limits" on page 90),
be sure to consider the affect that the humidifier has on
Delta T.
4. If a Bypass Humidifier is installed, mount the Discharge
Air Temperature Sensor downstream of the Bypass
Humidifier. See Fig. 13–14.
10
Fig. 9.
MCR32389