Asked by: Togarma Povill
home and garden smart home

Does the ecobee3 need AC wire?

Last Updated: 18th June, 2020

Your ecobee3 does not need them. Some thermostats do not have a C-wire. The C-wire is used to reliably provide power to the thermostat. In this case, the PEK can use the existing wires to power your thermostat.

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Keeping this in consideration, do you need AC wire for thermostat?

The C wire, or “common wire” enables the continuous flow of 24 VAC power to the 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. Thermostat wire is just a big spool of bundled, color-coded wires.

Furthermore, will ecobee work with 2 wires? ecobee thermostats require a C (common) wire to power on. If you only have two wires at your current thermostat, there are a few installation options available, depending on your application. Note: You will not be able to install the Power Extender Kit (PEK) with heat-only 2-wire systems.

People also ask, what wires does ecobee need?

Depending on your system, the Power Extender Kit (PEK) included in the box with every ecobee may be able to provide a C wire connection.

How many wires do I need to install an ecobee thermostat?

Type of system Minimum wires needed PEK compatible?
Cooling-only 4 (R, C, G, Y) 3 if PEK is used Yes

Is RC same as C wire?

RC and RH. If the air conditioning thermostat has one transformer to power both the heating and cooling system, then the wire from the transformer goes directly to the RC terminal and is called the RC wire. Effectively there isn't a second RH wire, although there is an RH terminal.

Related Question Answers

Maurita Mewe


Can I use the G wire for the C wire?

Using the g-wire as a c-wire
If you can not find an unused wire or common wire, you can also use for fan wire or g-wire as a common wire.

Jianan Wohllebe


What can I use if I don't have AC wire?

Even though it comes with an adapter for missing c-wires, ecobee is what we'd pick even for systems with a c-wire. If you've got a 24v HVAC system but no C-wire, check out the ecobee product line. Every ecobee ships with an adapter that you can install yourself at your furnace to make up for a missing C-wire.

Pancracio Uriondo


How many wires does a thermostat need?

In the most basic system, this functionality is provided by use of a fan center relay, and the low voltage wiring to the thermostat now will require a minimum of three wires (for heat only units) and four wires (for heat / cool / fan) for control. This additional terminal is labeled 'G' in the thermostat.

Harry Foerster


Is the C wire a ground?

C stands for common. The common wire is the ground or negative wire. To complete the circuit that provides power to the thermostat you need a positive and negative wire from the 24V transformer. Some thermostats have batteries that power them and they serve only as a switch to operate the heating or cooling unit.

Gilbert Gueto


What color is the common wire?

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.

Leopoldo Gallinat


Does low battery affect thermostat?

Most models of programmable thermostats will display or flash some sort of low battery symbol when the batteries begin to run low. At this point, the thermostat can no longer control the HVAC system. This could possibly lead to excessive heating or cooling of your home, or no heating or cooling at all.

Toribia Mardura


What is a common wire HVAC?

In most cases, Google Nest thermostats can charge their built-in battery using your system's heating and cooling wires. A common wire is simply a wire that's dedicated to delivering constant power to your thermostat. Unlike the other wires connected to your thermostat it doesn't control heating or cooling functions.

Guilhem Udabe


Which is better nest or ecobee?

ecobee4 Smart Thermostat with Built-In Alexa, Room Sensor Included. The Ecobee 4 is an affordable smart thermostat with Alexa built in. If you prefer the same temperature-adjustment technique used for conventional thermostats, the Nest Learning Thermostat is a good choice. The Ecobee4 utilizes a touchscreen.

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How do I install a WIFI thermostat without C wire?

To add a C-wire to your furnace, follow these steps:
  1. Turn off the breaker for the furnace.
  2. Remove the access panel and locate the wires that connect to the thermostat.
  3. Disconnect the thermostat wire from the G terminal.
  4. Note: If you have both central heat and air, then you'll need to make a jumper using an 18 AWG wire.

Xabi Entwistle


Can you install ecobee yourself?

Can I install it myself? Sure thing! Installation typically takes 45 minutes or less. Simply follow the instructions included in the ecobee mobile app, or in the manual that was included in the box with your ecobee.

Myryam Stampf


Hongwei Alomoto


How do you know if you have C wire?

It is easy to see if you already have a c-wire connected to your system. Simply remove your current thermostat face from its baseplate and look for the terminal labeled with the letter “c.” If this terminal has a wire attached to it, you have an active “c-wire.”

Eduardas Resti


What is the C wire?

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. It is often labeled as “c” on thermostat backplates.

Dalila Thiedmann


How do you run an AC wire?

Start by removing the access panel on the furnace, and locating the thermostat wires. Remove the wire from the G terminal, and connect it to the C terminal. Using a short piece of 18 AWG wire, make a jumper and connect it between the Y and G terminals (this is only required if you have both heat and central air).

Mimi Daly


Where do you connect the C wire on a boiler?

When a thermostat calls for heat, the valve for that zone opens, and the boiler is also signaled via the auxiliary switch in the valve. To get a C wire to one or more of the thermostats, you'll simply run a wire from the other side of the transformer on the wall.

Waheed Reichel


Does the Ecobee have a battery?

The Ecobee comes with one wireless sensor, which is powered by a CR2032 coin-cell battery; the company says it should last about 4 years. When the battery runs low, you'll receive an alert.

Khaled Zhadaev


What is a fast stat?

The FAST-STAT Common Maker Thermostat Wire Extender eliminates the need to install new cables when upgrading old thermostats to newer Wi-Fi thermostats. The Common Maker uses existing cable to add a "C" connection in a Wi-Fi thermostat allowing for 24 volt power source to be added.

Haresh Pello


How much does it cost to install ecobee?

Ecobee 4 is $250 full price, so they want $900 to install.

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Where does e wire go on ecobee4?

The E wire normally connects to the ecobee's W1 terminal.