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THX9321 PRESTIGE
®
2.0 AND THX9421 PRESTIGE
®
IAQ 2.0 WITH EIM
17 68-0311—01
2030 What Terminals are
Wired to Radiant
Heat?
None
U1
U2
U3
Default varies
based on
previous
selections
Both No This ISU is only displayed when ISU 2010 Heating
Equipment Type is Geothermal Radiant Heat.
Geothermal Radiant Heat must be wired to a
universal terminal (U1, U2, or U3).
U1, U2 and U3 are normally open dry contacts when
configured for a stage of Heat. U1, U2 and U3
require power from the system transformer or a
separate transformer.
U3 is only available on the Equipment Interface
Module (EIM).
2040 What Terminals are
Wired to Radiant Heat
- Stage 2?
None
U1
U2
U3
Default varies
based on
previous
selections
Both No This ISU is only displayed when ISU 2010 Heating
Equipment Type is Geothermal Radiant Heat.
Geothermal Radiant Heat must be wired to a
universal terminal (U1, U2, or U3).
U1, U2 and U3 are normally open dry contacts when
configured for a stage of Heat. U1, U2 and U3
require power from the system transformer or a
separate transformer.
U3 is only available on the Equipment Interface
Module (EIM).
2050 Geothermal Forced
Air System
None
Used for Cooling Only
Used for Heating and Cooling
Used for Heating
and Cooling
Both No This thermostat has the capability of controlling
Geothermal Radiant Heat, Geothermal Forced Air
and Backup Heat.
If this thermostat is not controlling the Geothermal
Forced Air System, select None. This setting is
typically used if the thermostat is only controlling
Geothermal Radiant Heat.
If this thermostat is using the Geothermal Forced
Air System for cooling and not for heating, select
Used for Cooling Only.
If this thermostat is using the Geothermal Forced
Air System for both heating and cooling, select
Used for Heating and Cooling.
2060 Reversing Valve O/B O (O/B on Cool)
B (O/B on Heat)
O/B on Cool Both No Only displayed if the equipment type is Air to Air
Heat Pump, Geothermal Heat Pump or Geothermal
Radiant Heat.
2070 Cool Stages /
Compressor Stages
1-4 1 if ISU 1010 is
Residential
2 if ISU 1010 is
Commercial
Both No Conventional:
Cool Stage 3 and 4 are only available if ISU 1010 is
Commercial.
Cool Stage 3 and 4 must be wired to a universal
terminal (U1, U2 or U3).
Heat Pumps:
Maximum of 2 Compressor Stages for heat pump
systems.
2020,
2070
Heat Stages / Backup
Heat Stages
1 - 3 Default is 1 stage
if ISU 1010
Application is
Residential
Default is 2
stages if ISU
1010 Application
is Commercial
Both No Maximum of 3 Heat Stages for conventional
systems.
Maximum of 2 Backup Heat Stages for systems with
more than 1 heating equipment type.
Table 2. Installer Setup (ISU) Table. (Continued)
ISU
Number Installer Setup Name Settings Default
Residential,
Commercial
or Both
Requires
EIM Notes