Honeywell RTH8500WF Wi-Fi Series Quick Start Manual page 12

1.12 Determine your heating/cooling system type
Important! Heating/cooling system type must be set so that your thermostat
operates properly and does not damage your system.
1.12a If you have a traditional system (natural gas forced air with A/C), your
thermostat is set up by default to control this system.
Go to Step 2
1.12b If your system is:
• Multistage equipment
• Any type of heat pump
• Hydronic
• Other
You MUST change the system type by setting system function 0170.
See "Setting functions and options" in the User Guide.
Not sure of your heating/cooling system type?
Refer to FAQ on wifithermostat.com/support
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