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
Amazon.com: Honeywell Home CT410B Manual 4 Wire Premium Baseboard/Line Volt Thermostat CT410B1017 : Everything Else
Thermostat wiring color code decoded - YouTube
How to replace a 4 wire thermostat - YouTube
How do i hook up a new 5 wire cable to an existing 4 wire furnace - Home Improvement Stack Exchange
Thermostat Wiring Explained! How To, Color Coding, Types & More
Cync Thermostat Wiring Configuration and Installation Guide
Decoding Thermostat Wiring Colors: Essential Guide for DIY Installation
Help with Wiring a Vintage 4-Wire Honeywell Thermostat - DoItYourself.com Community Forums
Thermostat Wiring to a Furnace and AC Unit! Color Code, How it Works, Diagram! - YouTube
HVAC PROBLEM SOLVER
Fast-Stat 1000 and Common Maker - Installation Guide – Simple
How to Upgrade to a Smart Thermostat with Four Wires | This Old House: Live - YouTube
4 Wire Thermostat Wiring Color Code — OneHourSmartHome.com
Cync Thermostat Wiring Configuration and Installation Guide
AprilAire 3-Wire to 4-Wire Adaptor
HOW TO INSTALL A 240 VOLT 4 WIRE WALL THERMOSTAT FOR A BASEBOARD HEATER (S) - YouTube
hvac - How can I modify a 4 wire thermostat to a new thermostat requiring c wire? - Home Improvement Stack Exchange
How to modify a 4-wire thermostat to a new ther mostat requiring a C wire - Quora
These are the wires I have behind my thermostat. Can I use a WiFi thermostat? : r/smarthome
4 Wire Thermostat Color Code and Wiring - PICKHVAC
hvac - How can I modify a 4 wire thermostat to a new thermostat requiring c wire? - Home Improvement Stack Exchange
How To Wire 4-Wire Thermostat | Storables
Nest thermostat with 4 wire system : r/hvacadvice
