I am replacing an old Honeywell thermostat heat only. The wires are not labeled and no label on the terminal. What would the brass terminal wire color be and what color would
![Newbie: Any way to add a c wire to existing transformer or wires? Do I need a new transformer with a “c” terminal? (Trying to connect a Wi-Fi thermostat to control boiler) : Newbie: Any way to add a c wire to existing transformer or wires? Do I need a new transformer with a “c” terminal? (Trying to connect a Wi-Fi thermostat to control boiler) :](https://i.redd.it/7yxznh8zs8z71.jpg)
Newbie: Any way to add a c wire to existing transformer or wires? Do I need a new transformer with a “c” terminal? (Trying to connect a Wi-Fi thermostat to control boiler) :
![Old thermostat works, but I can't get the Honeywell T9 to work. T9 require C Wire that was not in the wall. I added C wire & RC wire via plug-in 120v Old thermostat works, but I can't get the Honeywell T9 to work. T9 require C Wire that was not in the wall. I added C wire & RC wire via plug-in 120v](https://i.redd.it/qgn9tccrp6a91.jpg)
Old thermostat works, but I can't get the Honeywell T9 to work. T9 require C Wire that was not in the wall. I added C wire & RC wire via plug-in 120v
![Old Honeywell 2 wire AC thermostat (with 1 extra wire behind) - can I modernize this with Ecobee? : r/ecobee Old Honeywell 2 wire AC thermostat (with 1 extra wire behind) - can I modernize this with Ecobee? : r/ecobee](https://i.redd.it/old-honeywell-2-wire-ac-thermostat-with-1-extra-wire-behind-v0-zgb7bnf4hv2b1.jpg?width=3024&format=pjpg&auto=webp&s=260717dc10e09aa7edef141b700365ef3292e75f)
Old Honeywell 2 wire AC thermostat (with 1 extra wire behind) - can I modernize this with Ecobee? : r/ecobee
![Honeywell THP9045A1023 Wiresaver Wiring Module for Thermostat - Programmable Household Thermostats - Amazon.com Honeywell THP9045A1023 Wiresaver Wiring Module for Thermostat - Programmable Household Thermostats - Amazon.com](https://m.media-amazon.com/images/I/71pGJ8WX0aL.jpg)