Videos of ac thermostat wiring with l port Click to view on YouTube5:39Thermostat Wiring to a Furnace and AC Unit! Color Code, How it Works, Diagram!7 views · 2 months agoYouTube › AC Service Tech LLCClick to view on YouTube20:17Air Conditioner Thermostat Wiring and Colors Code18K views · Aug 9, 2016YouTube › Richard AshworthClick to view on YouTube3:21Wiring a Single 24v Thermostat to Control Two HVAC Systems- Heater and Air Conditioner19K views · Apr 3, 2016YouTube › AC Service Tech LLCClick to view on YouTube10:35Thermostat Wiring Explained!1 views · 1 month agoYouTube › Benjamin SahlstromClick to view on YouTube11:06Basic Thermostat Wiring44K views · 4 months agoYouTube › Word of Advice TVClick to view on YouTube1:45Central Air Conditioning Information : How to Wire a Digital Thermostat223K views · Jan 27, 2012YouTube › essortmentSee more videos of ac thermostat wiring with l port Guide to Thermostat Wiring Color Code: making install Thermostat wire is made of multiple strands of solid copper wire, each wrapped individually with a colored shell and enclosed together inside a protective sheathing. During installation, the wires are connected to one board that sends certain data through each wire to the thermostat. The system will not operate correctly if the wires are incorrectly  Heat Pump Thermostat Wiring - Air Conditioning Systems Heat pump thermostat wiring - A typical wire color and terminal diagram. As shown in the diagram, you will need to power up the thermostat and the 24V AC power is connected to the R and C terminals. The color of wire R is usually RED and C is BLACK. C is known as the common terminal. These two connections will ensure that there is power to the thermostat that you are operating.