What color wire goes where on a Honeywell thermostat?

Meaning of Wiring Terminal Letters



W (white) controls the auxiliary heating elements. Y (yellow) controls the compressor on the cooling system. G (green) controls the fan. C (blue or black) provides a return path to the transformer.

What color wire goes where on a thermostat?





This is the most typical thermostat wiring style, and it applies to systems that regulate both heat and air conditioning. The wires are typically arranged as follows: red for 24-volt hot, white for heat, yellow for cooling, green for the fan, and blue for common (although the common wire may be a different color).

How do I wire a Honeywell thermostat?

Quote from the video:
You can pull the thermostat off the wall or basically off the base of it. Just look around the thermostat or just try prying on it gently from all sides until it comes off this one comes off pretty.

Where does the red and white wire go on a Honeywell thermostat?

The white wire is usually connected to the “W” terminal. The thermostat acts as a switch, like a light switch. The Red to white switch turns on the heat. Red to Green turns on the fan, Red to Yellow turns on the air conditioner.

What are the wires on a thermostat?

Thermostat Wiring Tips

  • The W wire is connected to your heating system. …
  • The Y wire is yellow and connects to your air conditioning compressor.
  • The G wire is green and connects to the fan.
  • Rc and Rh: The red wire(s) are the power source for your thermostat.

What color is the C wire?





Blue wires

Blue wires are also called “C” wires because they are the Common wire. C wires are necessary for any “smart” thermostat that needs to be connected to a power source 24/7, regardless of your heat pump type.

What is white wire on thermostat?

The white wire underneath your thermostat connects to your heating system. It terminates at your air handler or furnace. The white wire connects to terminal W in industry-standard thermostats.

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 are S1 and S2 wires on thermostat?



S, S1, S2: These wires run directly outside and provide outdoor temperature information to the thermostat.

Does the red wire go to RC or RH?

There is no standard for the colour of the RH wire, but most units use a red one. The RC wire, on the other hand, refers to “red cooling”. It’s the same with the RH wire in that it powers the thermostat. For the RC, it powers the cooling system.

How do you wire a 4 wire Honeywell thermostat?

Quote from the video:
W is for white o. Or B is for orange or blue which here's the trick. When you have an older thermostat wire that runs the blue wire in there the four wire pair you want to hook the blue to the yellow.

Where is the C wire on a thermostat?



Quote from the video:
So it's fairly simple to tell if you have a/c wire or not firstly the purpose of a/c wire is basically for the newer thermostats. As either has a backlit display or has Wi-Fi functionality.

Does Honeywell thermostat require C wire?

A common wire (C-Wire) provides Wi-Fi thermostats continuous power by connecting it to a heating and cooling system (e.g. furnace). C-Wires are required on most Honeywell Wi-Fi thermostats, with the exception of the Smart Round Thermostat (formerly known as the Lyric Round).

Is RC and C wire the same?

Typically, the wires that provide the power (often called the “hot” wires) are labeled Rc (cooling) and Rh (heating). They provide a source of 24V power coming from the HVAC control board. Sometimes they are separate wires and require separate connections. Other times they are the same wire.

How do I run C wire?

Quote from the video:
Run actual thermostat wire in the all and connect. It to the existing thermostat wire if you've got an extra wire or if you want to fish some new ones in the wall.

Does C wire have voltage?



A C-wire, or a common wire, runs from your low voltage heating system (24v) and carries continuous power to your thermostat. In today’s electric market, most newer heating and cooling systems have C-wires, which guarantees compatibility for the installation of all smart thermostats.

How do you hook up a C wire to a furnace?

Option 1: Add a C Wire to Your Furnace



Remove the access panel from the furnace and locate the thermostat wires and terminals. Connect an 18 AWG wire to the C terminal at the furnace. Next, remove the thermostat face plate. Now, run the new C wire from the furnace to the back of the new thermostat.

How do I know if my C wire is working?

Easiest way to check is pull any batteries out of the old thermostat and look for a wire (normally blue) is connected to the C spot. If the old unit supports being powered by the common wire, then the unit will turn on without batteries.

How long is a strand of C wire?

Blade size: length=65 mm, width=21 mm. Spacing of blades: 100 mm C/C. Coil diameter: 3′-2″ or 960 mm.

What has C wire but no power?



A “C” wire does not supply power it is used as a return wire (a grounded or neutral conductor). You will also need a power source conductor, it’s usually red. So your thermostat should have at least five conductors labeled R-power, C-common, G-fan, Y-cool, W-heat and if you have a heat pump O-reversing valve.