THX9321 PRESTIGE
®
2.0 AND THX9421 PRESTIGE
®
IAQ WITH EIM
25
68-0311—02
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.
2080
What Terminals are
Wired to Cool -
Stage 3?
None
U1
U2
U3
Default varies
based on
previous
selections
Commercial No
Cool Stage 3 is only available if ISU 1010 is
Commercial.
Cool Stage 3 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
Cool. U1, U2 and U3 require power from a
system transformer or a separate
transformer.
U3 is only available on the Equipment
Interface Module (EIM).
Table 4. Installer Setup (ISU) Table. (Continued)
ISU
Number
Installer Setup
Name
Settings
Default
Residential,
Commercial
or Both
Requires
EIM
Notes