https://www.googlenestcommunity.com/t5/Nest-Thermostats/Nest-thermostst/m-p/627363#M121504 <P>My old thermostat had a black wire and red wire - which of these wires go in which slot on&nbsp; nest thermostat?</P> Fri, 21 Jun 2024 20:57:50 GMT ritu1 2024-06-21T20:57:50Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/Nest-thermostst/m-p/627363#M121504 <P>My old thermostat had a black wire and red wire - which of these wires go in which slot on&nbsp; nest thermostat?</P> Fri, 21 Jun 2024 20:57:50 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/Nest-thermostst/m-p/627363#M121504 ritu1 2024-06-21T20:57:50Z https://www.googlenestcommunity.com/t5/Nest-Thermostats/Nest-thermostst/m-p/627469#M121528 <P>The wire colour alone is not enough to determine where it needs to be connected.&nbsp;</P> <P>If you've not already done so I'd recommend checking your system is compatible:<BR /><STRONG><A href="https://support.google.com/googlenest/answer/9246656?sjid=12638830704742225188-EU" target="_blank" rel="noopener">Nest thermostat compatibility - Google Nest Help</A></STRONG></P> <P>Once you've checked that, use the correct app for setup. Use the Nest app for Nest Learning Thermostat and Nest Thermostat E models. Use the Google Home app for Nest Thermostat (2020 model). The app will guide you through the setup and tell you where to connect the wires.</P> Sat, 22 Jun 2024 14:17:38 GMT https://www.googlenestcommunity.com/t5/Nest-Thermostats/Nest-thermostst/m-p/627469#M121528 David_K 2024-06-22T14:17:38Z