5 Wire Thermostat Wiring (Any HVAC Device – Air Conditioners, Heat Pumps, Furnaces, etc.)
Red wire for power (24V).White wire for heating (connected to W or W1 terminal).Green wire for fans.Blue or yellow wire for cooling (connected to Y).Black wire for “C” or “Common” wire.
What are all the wires for on a thermostat?
The yellow wires underneath your thermostat connect to your compressor. They control your air conditioning system. The yellow wires terminate at your compressor contactor via an air handler. The yellow wires connect to the Y terminals on your thermostat.
Does thermostat wire color matter?
It is often blue or black, but in reality, the color of the wires in your thermostat doesn’t indicate their function – they are just shorthand to make installation a little easier. Some of the other wires powering your thermostat include: R-wire – Power, usually red. G-wire – Fan, usually green.
What are S1 and S2 wires on thermostat?
S, S1, S2: These wires run directly outside and provide outdoor temperature information to the thermostat.
What happens if you wire a thermostat wrong?
Potential consequences of improper installation could include: Electric shock. Blowing a circuit breaker. Damaging the thermostat unit, the electrical system or even the AC/furnace unit itself.
What is the Blue wire for on my thermostat?
The Blue or “C” Wire
C wires or varying colors apply to every thermostat, but blue C wires belong to thermostats attached to a heat pump. Blue wires are for heat pumps, like orange wires. This wire connects to terminal B on your thermostat.
What color is C wire?
The C wire’s color isn’t standardized, so its color can’t be guaranteed across all HVAC systems. It is most often either blue or black, unless the installer did their own rewiring to create a C wire. These are the most common colors and the labels used for thermostat wires: Blue or Black – C – The common wire.
What does R and W mean on thermostat?
W wire – heat. R wire – heat power. W wire – heat.
What do the letters mean on a thermostat?
Contrary to popular belief, the letters do not correspond to wire colors but rather are used to indicate the various function signals controlled by each wire.
What is the orange wire for on a thermostat?
Orange Thermostat Wires
You will only see an orange wire in your thermostat if your system has heating. These orange wires directly link to your outdoor condense that reverses valve operation from one setting to another. It is important to note that sometimes you will see a dark blue wire instead of orange.
What is the Y2 wire on a thermostat?
Y2 is the thermostat wire for second stage of cooling. Y wire is for the first compressor (air conditioner units) and Y2 wire is for the second compressors (air conditioner unit). Y2 wires apply only if you have two air conditioner compressor units running from one AC thermostat.
Do I need a jumper from R to RC?
If you have a wire in the R terminal, and another wire (not a jumper) in the RC terminal, you will not need to connect the R and RC terminals. See our Basic Wiring article for more info here.
What does RC and RH mean on a thermostat?
Rh stands for Red-Heat and Rc stands for Red-Cool. If you only have a single red wire the jumper between Rh and Rc are required for some heating and cooling hybrid systems depending on your thermostat. Yellow/Y is the AC compressor. White/W is the Heating element.
What is the G wire?
Refer to the thermostat manufacturer’s wiring diagram for more information. The G terminal is the one that controls the fan relay and can be used to turn the blower fan on or off. The RC terminal is a cooling power supply.
