Wiring for ac and dc power distribution branch circuits are color coded for identification of individual wires.
Ac control wiring colors.
Thermostat wiring colors code hvac control always follow the thermostat manufacturer s instructions whenever changing the thermostat.
In that case local custom dictates the optional wire colors.
Abyc cable wire color codes for yacht boat marine wiring there are multiple colors used for different wires and cables in different regions for ac alternating current single phase three phase and dc direct current for design and installation based on the local codes rules and regulations.
Dual transformer systems refer to a setup with a cooling and heating transformer.
Rc wires are only for air conditioning systems or dual transformer systems.
Red wires specifically rc wires are responsible for 24 hour volt ac power from your transformer.
These wires only connect to your cooling system.
For wires that will be 120 208 or 240 volts the following wiring color standards are used.
In some jurisdictions all wire colors are specified in legal documents.
Always turn the power off at the air handler and the condenser and make sure there is no voltage at the transformer before proceeding.