![Blue "C" wire is connected to "Y" on old thermostat. New thermostat has separate "C" hookup. Where does the blue wire go - "Y" or "C"? : r/Nest Blue "C" wire is connected to "Y" on old thermostat. New thermostat has separate "C" hookup. Where does the blue wire go - "Y" or "C"? : r/Nest](https://i.imgur.com/qa9UXyW.jpg)
Blue "C" wire is connected to "Y" on old thermostat. New thermostat has separate "C" hookup. Where does the blue wire go - "Y" or "C"? : r/Nest
![Google Nest Power Connector - Nest Thermostat C Wire Adapter - C Wire Adapter for Smart Thermostat - Nest Thermostat Accessories : Amazon.co.uk: Pet Supplies Google Nest Power Connector - Nest Thermostat C Wire Adapter - C Wire Adapter for Smart Thermostat - Nest Thermostat Accessories : Amazon.co.uk: Pet Supplies](https://m.media-amazon.com/images/I/71sTsWfScQS._AC_UF350,350_QL80_.jpg)
Google Nest Power Connector - Nest Thermostat C Wire Adapter - C Wire Adapter for Smart Thermostat - Nest Thermostat Accessories : Amazon.co.uk: Pet Supplies
![boiler - Where do I connect my C wire from my thermostat when there are two transformers? - Home Improvement Stack Exchange boiler - Where do I connect my C wire from my thermostat when there are two transformers? - Home Improvement Stack Exchange](https://i.stack.imgur.com/wO3qZ.jpg)