Where does the C wire go to?

Modern thermostats with Wi-Fi and backlit display, by contrast, need a steady supply of juice. The C wire, or “common wire” enables the continuous flow of 24 VAC power to the thermostat. Technically speaking, power flows from the R (red) wire, but not continuously (not on its own, anyway).

What color is the C wire on a thermostat?





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.

How do I find the C wire on my thermostat?

You should be able to pop the cover off of your thermostat with ease. When you open your thermostat, you can quickly identify your C-wire among five coloured wires by locating the wire (usually blue) connected to ‘terminal C. You may find there are fewer than five wires, or there is no wire attached to terminal C.

Can I connect C wire to ground?

Wiring to the ground @ any outlet would potentially work, but is not good practice,as many things could go wrong and possibly short or overload the circuits in your furnace controls, not good! Happy trails. Hello, and welcome to Home Improvement. Thanks for the answer; keep ’em coming.

How do I know if my C wire is working?





You should see 24 Vac. It could be as high as 29 Vac when nothing is running, and nothing will be with your thermostat removed. If you have the voltage then the C wire is real and you can continue. If not consider having your system updated to include it.

Why is my C wire not getting power?

Quick Check for an Existing C-wire:



If it has batteries, remove them. If the thermostat loses power it does not have a C-wire, and you may need an add-a-wire kit. If it doesn’t lose power, locate your breaker panel. Flip the breaker for the wall with the thermostat on it.

What is the C terminal on a thermostat?

What is the C Wire on a Thermostat? The c wire is an extra wire that can be used to provide a return path for continuous 24V power for any application. It’s normally used to provide a return path to power the thermostat. The “c” stands for common.

Can the C wire be brown?

The C, or common wire, provides smart thermostats with continual power. It’s usually blue, but it may also be black, brown or purple. The O or orange wire connects to your heat pump (if applicable).

Where does the orange wire go on a thermostat?



The Orange Wire



The orange thermostat wire links to your heat pump, if you have one. It terminates in your outdoor condenser for reversing valve operation from hot to cold. The orange wire connects to terminal O on your thermostat. The orange wire only applies to homeowners with an air-source heat pump.

Is the C wire a neutral wire?

The C wire is more like a neutral wire (in electrical terms) and it completes the electrical circuit between the furnace (or any heating system) and the thermostat, thus ensuring a flawless power supply to thermostat even when the furnace is OFF.

Can you connect C wire to transformer?

If you have a heat-only system connected to your Sensi thermostat, an easy option for adding a common, or c-wire, is to install a 24 VAC wall plug-in transformer. Transformers with 150-400mA output are the most widely available online and easily provide sufficient power for the thermostat.

How do I run C wire?



A C wire transformer has two output wires; connect one wire to Rc terminal and the other wire to the C terminal of your thermostat. Once you finish this connection, plug the transformer into your mains power outlet. The installation is complete now and the thermostat will be powered upon switching ON the power outlet.

How do you run a new C wire?

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.

Is C wire the same as RC wire?

1-2 of 2 Answers



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.

Where does R and RC wire go on nest?

An R wire can go into a Nest Learning Thermostat’s Rc or Rh connector. The Nest Thermostat E only has an R connector, which is typically where an R wire would go.

Does Nest Learning thermostat require C wire?



With a Nest Thermostat E or Nest Learning Thermostat, you’ll need to install a C wire if the thermostat has power issues or its battery often drains.

Does red wire go to R or RC?

If you have both an Rh (Red-heat for powering the heating) and an Rc (Red-cool for powering the cooling), then the R wire can be connected to either Rh or Rc. If you only have a single R wire, then it will only have an R connector, which is the connection you’ll use.