If your system has a C-wire, it might be in use or just tucked away behind your current thermostat. If your system doesn’t have a C-wire, you’ll need to run a new cable from your furnace to your thermostat to install most of the modern smart thermostat models.

How do you wire a C wire to a furnace?

Quote from the video:
Quote from Youtube video: One of these is gonna be Diggs wires they go to the thermostat. One of these is gonna be the wires that go to the AC compressor. And they come in through the top here.

Where does the C wire get its power?

WHAT IS A C-WIRE? 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.

What if there is no C wire for thermostat?

If your current thermostat didn’t need a C-wire, it (or a wire that can be used as a C-wire) might be rolled up inside the wall. This is more likely to be true if you see all the other color wires present. Line voltage thermsotat scenario: you have just two wires (white and red, probably), and they’re thick.

Where is the C wire on a thermostat?

Quote from the video:
Quote from Youtube video: But we're gonna go ahead and just pop the top off or pop the cover off your thermostat. Wherever you do that but mine has a little thing down here. And then we're have access to all the wiring.

Does C wire have voltage?

The C wire, a.k.a. the “common wire”, allows a constant flow of 24 VAC (volts AC) power to a smart thermostat. However, the C wire doesn’t provide the actual source of power to the thermostat. The wires that provide the source of power are the R wires (or hot wires).

How do I know if C wire is live?

Quote from the video:
Quote from Youtube video: Begin by putting one probe whichever probe you want on the rh wire and test every other wire with the other probe. One of the wires will show up is 24 volts and that is your c wire.

Is the common wire the hot wire?

Black wire: This is a hot wire that carries electricity from the power source to the first switch in a typical 3-way setup. It’s also called the “common wire” or the “line wire.” Unless the breaker is off, this black wire is always hot.

What color is common wire on furnace?

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.

Is neutral and common wire the same?

The common wire is normally the white wire, at least in the United States, and is often called the neutral wire. It’s also called common because all circuits in the house typically have the white wires tied together, which means every circuit has that wire in common.

Does a common wire have power?

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).

Can I tie the neutral and ground together?

No, the neutral and ground should never be wired together. This is wrong, and potentially dangerous. When you plug in something in the outlet, the neutral will be live, as it closes the circuit. If the ground is wired to the neutral, the ground of the applicance will also be live.

Is common wire hot or neutral?

White. The “common” is the “neutral” or “ground” wire, depending on the type of circuit. In normal US residential wiring, you’ll have a black “hot” wire, a white “neutral” or “common” wire, and a green or bare “ground” wire.

What happens if the neutral wire is not connected?

If the neutral wire disconnects, it would stop the flow of the electricity and break the circuit. The role of the neutral wire is to provide this path to the electrical panel to complete the circuit. The neutral wire is bonded to the earth ground inside the panel.

Where does the neutral wire go?

Neutral wire carries the circuit back to the original power source. More specifically, neutral wire brings the circuit to a ground or busbar usually connected at the electrical panel.

Does neutral wire need to be connected?

Except in very rare situations, all neutral wires in a box must be connected. The neutral is how the current flows back to the supply, so if you don’t connect a neutral to one fitting it won’t work. You could connect three in one connector, then three in another, and have a link between the two.