Installation Instructions

7
# ISU ISU Name ISU Options (factory default in bold)
205 Heating Equipment Type Conventional Forced Air Heat:
1 = Standard Efficiency Gas Forced Air
2 = High Efficiency Gas Forced Air
3 = Oil Forced Air
4 = Electric Forced Air
5 = Hot Water Fan Coil
Heat Pump:
7 = Air to Air Heat Pump
8 = Geothermal Heat Pump
Radiant Heat:
9 = Hot Water Radiant Heat
12 = Steam
Note: This option selects the equipment type your thermostat will
control. Note: This feature is NOT displayed if feature 200 is set
to Cool Only.
218 Reversing Valve O/B
0 = O (O/B in Cool)
1 = B (O/B in Heat)
Note: This option is only displayed if the Heat Pump configured.
Select whether reversing valve O/B should energize in cool or in
heat.
220 Cool Stages / Compressor
Stages 200=Conv / 200=HP
0, 1
Note: Select how many Cool or Compressor stages of your
equipment the thermostat will control. Set value to 0 if you do not
have Cool Stage/Compressor Stage.
221 Heat Stages / Backup Heat
Stages
Heat Stages: 1
Backup Heat Stages: 0, 1
Note: Select how many Heat or Aux/E stages of your equipment
the thermostat will control.
230 Fan Control in Heat 1 = Equipment Controls Fan
2 = Thermostat Controls Fan
Note: This ISU is only displayed if ISU 205 is set to Electric Forced
Air or Fan Coil.
300 System Changeover
0 = Manual
1 = Automatic
Note: Thermostat can automatically control both heating and
cooling to maintain the desired indoor temperature. To be able to
select “automatic” system mode on thermostat home screen, turn
this feature ON. Turn OFF if you want to control heating or cooling
manually.
303 Auto Changeover Differential 0 °F to 5 °F
0.0 °C to 2.5 °C
Note: Differential is NOT deadband. Differential means how
far past the setpoint before switching to the mode selected.
Deadband setup is not an option. Honeywell uses an advanced
algorithm that fixes deadband at 0 °F. This is more advanced
than previous thermostats.
340 Backup Heat Droop
(TH4210U only)
0 = Comfort
2 = 2 °F
3 = 3 °F
4 = 4 °F
5 = 5 °F
6 = 6 °F
7 = 7 °F
8 = 8 °F
9 = 9 °F
10 = 10 °F
11 = 11 °F
12 = 12 °F
13 = 13 °F
14 = 14 °F
15 = 15 °F
Advanced setup options (ISU) (continued)