Honeywell PRESTIGE THX9321 - Manual (Page 28)

THX9321 PRESTIGE ® 2.0 AND THX9421 PRESTIGE ® IAQ WITH EIM
68-0311—02 28
2170 What Terminals are
Wired to Backup
Heat - Stage 2?
None
U1
U2 Default varies
based on
previous
selections
Both No THX9321 Thermostat Only:
This ISU is only displayed on the THX9321
thermostat when it is wired directly to the
equipment (Equipment Interface Module is
NOT used).
The thermostat can support up to 2 backup
heat stages for heat pump applications.
When there are 2 backup heat stages,
backup heat stage 2 must be wired to U1 or
U2.
U1 and U2 are normally open dry contacts
when configured for a stage of Heat. U1
and U2 require power from a system
transformer or a separate transformer.
2180 Backup Heat Type Electric Forced Air
Standard Efficiency Gas Forced Air
High Efficiency Gas Forced Air
Oil Forced Air
Hot Water Fan Coil
Hot Water Radiant Heat
Other Electric Forced
Air
Both No This ISU is only displayed when ISU 2010
Heating Equipment Type is Air to Air Heat
Pump, Geothermal Heat Pump or
Geothermal Radiant Heat and there is at
least one stage of backup heat.
See “Heat Pump and Backup Heat
Operation” beginning on page 100.
2190 External Fossil Fuel
Kit
Thermostat Controls Backup Heat
External Fossil Fuel Kit Controls
Backup Heat
Thermostat
Controls
Backup Heat
Both No This ISU is only displayed when ISU 2010
Heating Equipment Type is Air to Air Heat
Pump, Geothermal Heat Pump or
Geothermal Radiant Heat and ISU 2180
Backup Heat Type is Standard Efficiency
Gas Forced Air, High Efficiency Gas
Forced Air or Oil Forced Air.
2200 Backup Heat
Operation
NOT allowed to Run with Heat
Pump
Allowed to Run with Heat Pump
Default varies
based on
previous
selections
Both No This ISU is only displayed when ISU 2010
Heating Equipment Type is Air to Air Heat
Pump, Geothermal Heat Pump or
Geothermal Radiant Heat and ISU 2180
Backup Heat Type is Hot Water Fan Coil or
Other.
Not Allowed to Run with Heat Pump: The
thermostat turns off the heat pump when it
calls for backup heat.
Allowed to Run with Heat Pump: The
thermostat keeps the heat pump on when it
calls for backup heat.
Table 4. Installer Setup (ISU) Table. (Continued)
ISU
Number
Installer Setup
Name Settings Default
Residential,
Commercial
or Both
Requires
EIM Notes