How to Install Ecobee without a C Wire

Ecobee installation without a C Wire is possible, even though a C wire enables the continuous flow of 24 VAC power(Volt Alternating Current) to the Thermostat.

This wire runs all the way from your furnace to your Thermostat, but it can still be done without, which is why this guide will take you through the process of Ecobee installation without a C Wire.

The wire is supposed to be called a “common”‘ wire, but I guess its abbreviation C wire sounds cool. So a C wire is mainly called so because every Wi-Fi thermostat needs to have one, as it provides continuous power to the Thermostat by connecting it to a heating and cooling system. 

Being able to connect your home’s Thermostat to a Wi-Fi connection is a big deal because that is what gives you the liberty to control your smart Thermostat remotely, even when you are not home, and it’s also a way to start building a smart home as many smart thermostats are able to sync with other smart home devices such as locks, cameras and more.

Usually, the C wire is blue-coloured, and it’s connected to the C terminal of your Thermostat, where it constantly provides a power supply to the Thermostat that helps in recharging its internal battery.

Not having a C wire means the Thermostat won’t get the necessary dose of power supply as it should, and this can very well alter the operation of the HVAC system, which is capable of damaging various components because if the Thermostat doesn’t get enough input power, it won’t be able to control other components of the system properly.

This will, therefore, lead to random failures and activations of the system. This is why there is so much fuss about a C wire, as it is a necessary component in any thermostat. So, how then can one carry out an Ecobee installation without a C wire?

Types of Ecobee Models

Before we look into Ecobee Installation without a C wire in much detail, we must note that there are three different types of Ecobee models;

  • The newly released, Ecobee smart thermostat (5th Gen),
  • The most popular, Ecobee 4
  • The budget-friendly, Ecobee 3 Lite.

In this guide, we will discuss the three different models of Ecobee installation without a C wire. You will need the C wire adapter that does the job of a traditional C wire. So we that, your Ecobee Thermostat still gets constant power supply as should. The C wire adapter does the same thing by taking power from your wall socket. 

From here, we will give a step-by-step procedure on how to carry out an Ecobee installation without a C wire on the different Ecobee models, beginning with the Ecobee Smart Thermostat.Ecobee Installation Without a C Wire

Ecobee Installation without a C Wire (Ecobee Smart Thermostat)

The Ecobee Smart Thermostat is the most advanced device in the lot, as it is the first Ecobee Thermostat with Siri, and it also has Alexa built-in for hands-free control. The Thermostat can also be controlled via an iOS or Android device.

Its most outstanding features are the support for Spotify Connect and Bluetooth Streaming. The installing process for this smart Ecobee Thermostat goes thus;

  • Start by removing your current Thermostat (if you have one) to test if the wires still work.
  • Then, install the backplate of the Ecobee Smart Thermostat to the wall and by screwing it in.
  • Carefully connect the wires to their correct terminals i.e. the R wire (Red Wire) and the power wire, to the RC terminal. 
  • Connect the G wire (Green wire), the fan wire, to the G terminal.
  • Connect the OB wire, which is the orange or dark blue wire connected to the heat pump, to the OB terminal. 
  • Connect the Y1, Y2 and W1, W2 wires to their respective terminals.
  • Your adapter comes with two wires; connect one of the wires to the RH terminal and the other to the C terminal.
  • Plugin the transformer unit into a wall outlet.
  • Attach the thermostat unit, and your Ecobee Smart Thermostat blank screen will be up and running after completing the initial setup processes of the Thermostat.

Check out Why you are Experiencing Ecobee Not Turning ON

Ecobee Installation without a C Wire ( Ecobee 4)

The Ecobee 4 also holds its own in the lineup of Ecobee thermostats with features like the Alexa built-in. However, it lacks Alexa calling feature.

Below is the installation process of the Ecobee 4;

  1. Remove your existing Thermostat. Ensure that it works properly to check if all the wires still work.
  2. Install the backplate of the Ecobee4 on the wall.
  3. Draw out the wires from the wall through the backplate and begin the wire connecting process.
  4. The power wire, which is the red wire, goes to the RC terminal.
  5. The fan wire, which is the green wire, goes to the G terminal.
  6. The heat pump wire, which is an orange wire or dark blue for some systems, goes to the OB terminal.
  7. For thermostats with air conditioners, the Y1 and Y2 wires will be the yellow wires, and they are connected to the Y1 and Y2 terminals.
  8. If there are additional heater systems, the W1 and W2 wires, usually white or brown wires, are connected to W1 and W2 terminals.
  9. Since we are discussing Ecobee installation without C wire, that means the installation doesn’t include a C Wire, so we take the adapter wires and connect them to the RH and C terminals.
  10. Connect the transformer unit to a wall outlet, and close up the Thermostat and voila! Ecobee4 is installed and ready to be set up.

If you have a problem with your Ecobee Wi-Fi connection, kindly check out How to Fix Ecobee Won’t Connect to WiFi.

Ecobee Installation without a C Wire (Ecobee 3 Lite)

This offers all of the basic features, supports all smart home set-ups from Apple Homekit to Samsung SmartThings and is very budget-friendly.

The installation process here is quite similar to that of the other two. Just be sure to screw your backplate in correctly, then embark on the wire connections appropriately, and you are good to go.

So, this is how you can successfully carry out an Ecobee installation without a C wire.

Leave a Comment