⚠
warning Honeywell
Error Code 171
Set the date and time — the time and date are not properly configured on the thermostat.
? What Causes This
Time and date were not set during initial setup or thermostat was disconnected from WiFi.
✓ How to Fix It
Set the time and date manually on the thermostat using Menu > Clock and Menu > Date (see page 23 for instructions).
Source: page 27 of the official manual
From the manual
