Honeywell RTH8500 Series - Select System Type; Heating Fan Control; Heat Pump Changeover Valve; Heating Cycle Rate

33-00133ES—01 22
System setup
Function Settings & Options
0170
Select System
Type
If you are not sure of
your heating/cooling
system type or have
other questions,
go to
withermostat.com
1 Heat/cool: Gas, oil or electric heating with central air conditioning.
2 Heat pump: Heat pump without backup or auxiliary heat.
4 Heat only with fan: Gas, oil or electric heat without central air
conditioning.
5 Heat only (no fan): Gas, oil or hot water heat without central air
conditioning.
6 Cool only: Central air conditioning only.
7 Heat pump: Heat pump with backup or auxiliary heating.
8 Heat/Cool Multiple stages: 2 heat stages (wires on W and W2), 2
cooling stages (wires on Y and Y2).
9 Heat/Cool Multiple stages: 2 heat stages (wires on W and W2), 1
cooling stage (wire on Y).
10 Heat/Cool Multiple stages: 1 heat stage (wire on W), 2 cooling stages
(wires on Y and Y2).
How do I set my heating/cooling system type? (See page 20 for instructions.)
Function Settings & Options
Note: Depending on system settings, functions on this page might not appear.
0180
Heating Fan
Control
0 Gas or oil heat: Use this setting if you have a gas or oil heating system
(system controls fan operation).
1 Electric heat: Use this setting if you have an electric heating system
(thermostat controls fan operation).
0190
Heat Pump
Changeover Valve
(for heat pumps
only)
0 Cooling changeover valve: Use this setting if you connected a wire
labeled “O” to the O/B terminal.
1 Heating changeover valve: Use this setting if you connected a wire
labeled “B” to the O/B terminal.
0240
Heating Cycle
Rate
5 Gas or oil furnace: Standard gas/oil furnace (less than 90% efficiency).
9 Electric furnace: Electric heating systems.
3 Hot water or high-efficiency furnace: Hot water system or gas furnace
(more than 90% efficiency).
1 Gas/oil steam or gravity system: Steam or gravity heat systems.
0250
Heating Cycle
Rate Stage 2
How do I customize my heating/cooling system? (See page 20 for instructions.)
Function Settings & Options
0280
Backlight
0 Backlight off, then on for approximately 8 seconds after keypress.
1 Backlight always on low intensity, full bright after keypress.
0300
Manual/Auto
Changeover
See page 20 for
more information.
0 Manual changeover (Heat/Cool/Off).
1 Automatic changeover (Heat/Cool/Auto/Off). Automatically turns on Heat
or Cool based on room temperature. Note: System maintains minimum
3°F difference between heat and cool settings.
0320
Temperature
Format (°F/°C)
0 Fahrenheit
1 Celsius
0330
Automatic Daylight
Saving Time
Adjustment
0 Off
1 On
What other functions can I change? (See page 20 for instructions.)