Do I need to connect the blue wire on my thermostat?

The Blue or C Wire



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 the blue wire on a 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.

Where does the blue and black wire go on a thermostat?





This the Common Terminal, and usually, a blue or black wire is run to the transformer from this terminal to complete the circuit, and in some cases, provide power to the Thermostat. This terminal is found on thermostats designed to work with Heating Pumps and is used to power the defrost cycle on the heat pumps.

Is blue wire always common?

A blue wire is usually the common wire. Homeowners that have a heat pump, in general, have blue common wires (if there is no heat pump, then the color might be black). What is this? The wire connects to the B terminal and allows the thermostat to constantly be connected to the power source.

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.

Where do I connect the blue wire on my Nest Thermostat?

A brown wire is mostly likely a heat pump wire and should be connected to the O/B connector on the Nest thermostat. If the B wire is blue, it should most likely be connected to the C connector.

What do the colored wires mean 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).

Does Nest Thermostat need jumper wire?

Nest thermostats don’t use jumper wires



Instead of using jumper wires, Nest Learning Thermostats use an internal jumper between the Rh and Rc connectors.

What is the common wire on a thermostat?

The C-Wire, or “common wire” enables the continuous flow of 24 VAC power to the thermostat. It’s a wire that (if you have one) runs all the way from your furnace to your thermostat.

How do I bypass the C wire on my thermostat?


Quote from Youtube video: Add a jumper wire between the Y and G. Terminals. If there's already wires attached just leave them be go ahead and push all the wires in. And close the backplate.

Where do I connect the C wire on my furnace?



Quote from the video:
Quote from Youtube video: You would typically connect. This a/c wire to be the C terminal on the board on the control board on in the furnace.

How do I find the C wire for my thermostat?

Quote from the video:
Quote from Youtube video: Likely there is gonna be a fifth wire tucked into the wall I'm thinking that's going to be our C wire most likely because as you can see we have a green a yellow a white in a red.

What is the C wire?

What is a 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).

Can I use RC wire as C wire?



No the Rc is the red wire. You need 5 wires or more for this to run with all the functions. You can use one of the other wires but you have to drop control of the fan. It will only come on when furnace comes on.