THX9321 & THX9421 Product Data
Table Of Contents
- Application
- Features
- Contents
- Specifications
- System Installation
- Installation Options
- Guidelines for Installing RedLINK Devices
- Installing Equipment Interface Module (if used)
- Wiring 24 Vac Common
- Selecting Discharge and Return Air Temperature Sensor Mounting Locations
- Selecting Return Air Temperature Sensor Mounting Location
- Installing Discharge and Return Air Temperature Sensors
- Selecting Thermostat Location
- Installing Wallplate
- Power Optional REDLINK™ Accessories
- Performing Initial Setup
- Linking Thermostat to Equipment Interface Module (if used)
- Linking RedLINK™ Accessories
- Completing Initial Setup
- Adding RedLINK Accessories to the Thermostat
- Locating the Connect Buttons on RedLINK Accessories
- Finding Your Password (Date Code) to Access Installer Options
- Installer Options
- Making Changes to Installer Setup
- Installer Tests
- Operation
- Setting the time/date
- Setting the fan
- Setting system mode
- Preset Energy-Saving Schedules
- Adjusting program schedules
- Overriding schedules: residential use
- Overriding schedules: commercial use
- Viewing equipment status
- Setting vacation hold: residential use
- Setting holiday/event schedules: commercial use
- Setting custom events: commercial use
- Setting holiday schedule: commercial use
- Setting holiday override: commercial use
- Initiating occupancy mode: commercial use
- Remote setback: commercial use
- Adjusting humidification settings
- Adjusting dehumidification settings: residential use
- Adjusting dehumidification settings: commercial use
- Adjusting ventilation settings
- Customizing screen color
- Setting preferences
- Cleaning the thermostat screen
- Adjusting security settings
- Viewing dealer information
- Advanced Features
- Installer options
- Using the temperature display
- Using the humidity display
- Universal Outputs (U1, U2, U3)
- Universal Inputs (S1, S2, S3, S4)
- Alerts and Diagnostics
- Heat Pump and Backup Heat Operation
- Indoor Air Quality (IAQ) Control
- IAQ Reminders
- Customizable Reminders
- USB Port
- Commercial Features
- Overriding schedules: commercial use
- Setting holiday/event schedules: commercial use
- Setting custom events: commercial use
- Setting holiday schedule: commercial use
- Setting holiday override: commercial use
- Initiating occupancy mode: commercial use
- Ramp Rates
- Custom Names
- Remote Setback
- Economizer and Time of Day (TOD) Operation
- Pre-Occupancy Purge
- Battery Replacement
- Optional Accessories
- Portable Comfort Control
- Remote Indoor Sensors
- Backup Control
- Replacing a Thermostat
- Replacing an Equipment Interface Module
- Wiring
- EIM Wiring Diagrams
- THX9321 Thermostat Wiring Diagrams
- THX9321 Thermostat Wiring Diagrams Using Universal Relays to Control Heating or Cooling
- Wiring IAQ Equipment or a Heat/Cool Stage to the Universal Terminals
- Economizer Module Wiring Diagrams
- Wiring C7089U1006 Outdoor Sensor
- Wiring guide — Wired Indoor Sensors
- Zoning
- Troubleshooting
- Regulatory Information
THX9321 PRESTIGE
®
2.0 AND THX9421 PRESTIGE
®
IAQ WITH EIM
68-0311—02 106
5. Select whether the U1, U2, or U3 terminals are Normally
Open or Normally Closed. See Fig. 220.
• Normally Open – contacts are normally open and will
close during a call for dehumidification
• Normally Closed – contacts are normally closed and
will open during a call for dehumidification.
Fig. 220.
6. Set the Overcooling Limit. See Fig. 221. Options:
• 0 °F to 3 °F (A/C with Low Speed Fan)
• 1 °F to 3 °F (A/C with High Speed Fan)
Fig. 221.
NOTE: ISU 10140 gives the option to lockout ventila-
tion on calls for dehumidification. This helps
maintain the desired humidity level.
Dehumidification using a Whole House
Dehumidifier
The Whole House Dehumidifier option requires a dedicated
unit for dehumidification. The thermostat can be set to control
dehumidification in all modes (Heat, Off, Cool [ISU 9120]).
Set up Dehumidification With Whole House
Dehumidifier
Some screens shown in this section may not appear on the
thermostat, depending on how you set up dehumidification.
1. Select the Dehumidification Equipment in ISU 9000. See
Fig. 222.
Fig. 222.
2. If optional remote wireless indoor sensors are installed,
you can choose which sensor you want to use for dehu-
midification control. For example, you can use one sen-
sor for humidification control, and another for
dehumidification. See “Wireless Indoor Sensor” begin-
ning on page 130 for more information.
Fig. 223.
3. If you are sensing humidity from two separate locations
(one for humidification and another for dehumidification),
you can select which humidity reading to display on the
home screen. See “Wireless Indoor Sensor” beginning
on page 130 for more information.
Fig. 224.