Ecobee3 vs Ecobee4 – Everything You Need to Know

Ecobee keeps taking steps forwards in giant leaps. With their latest smart thermostat, the Ecobee4, they have included integrated technology with Amazon Alexa.

In case you were wondering, it’s pronounced “YI-co-bee” according to the manufacturer.

In this smart thermostat review, I will sort out all the new features of the Ecobee4 and compare it in a side by side showdown with the Ecobee3.

To read the full review and get all the in-depth details, continue reading the entire article below. If you just want to know what I think: I think the improvements implemented by Ecobee make the Ecobee4 the better selection over the Ecobee3.

The Differences between the Ecobee3 and Ecobee4

  • Amazon’s Alexa is built into the Ecobee4, whereas Ecobee3 is compatible with Alexa.
  • Physically the Ecobee4 is larger, thicker and heavier than the Ecobee3.
  • The back plate has been redesigned in the Ecobee4, and a few wire terminals have been relocated.
  • There is a new icon on the Ecobee4 LCD touch screen for voice control options and menus.
  • Ecobee 4 has a new LED light to indicate that Alexa is ready.

The Similarities in the Two Ecobee Thermostats

  • Each model has mobile app integration.
  • Both the Ecobee3 and Ecobee4 both control all HVAC systems including gas, electric and oil.
  • The thermostats both come with a room sensor.
  • The Ecobee3 and Ecobee4 both support voice controls via Amazon Echo, Google Home, IFTTT, and others. Also, both work with Apple HomeKit.
  • Each of the models has an included Power Extender Kit for homes without a C wire.
  • Energy saving modes allow you to save up to 23 percent on your home energy bill, annually.
  • Both thermostats are hardwired and do not require battery operation.
  • The LCD touchscreen is a staple for each unit.

The Comparison Chart

  Ecobee3 Ecobee4
LCD Touch Screen Yes Yes
Humidifier, Dehumidifier, Ventilator Support Yes Yes
Smart Device Support Yes Yes
Amazon Alexa Connectable Built-in
Power Extender Kit Included Included
Room Sensors 1 Included 1 Included
Mobile App Control Yes Yes
Speaker No Yes
Far Field Voice Recognition No Yes
Motion Sensors Yes Yes
Price Check on Amazon Check on Amazon

Features and Options

Let’s take a deeper look at some of the features and options in both the Ecobee3 and the Ecobee4.

1. Room Sensors

The room sensors have not had any upgrades with the new thermostat, however, since Ecobee released the Ecobee4, all models now include at least one room sensor.

The room sensors are wireless sensors you place around your home in rooms you use often. Most users place them in the living room, bedrooms and kitchens. These sensors will take the temperature of the room they are in to report to the thermostat so it can better gauge the average throughout the home.

They will also detect motion so when you enter the home the thermostat can adjust the cycle using the Home and Away mode, or adjust the temperature to your specifications where ever you go in the home using the Follow Me mode.

Bottom Line: A tie. Room sensors add to the energy efficiency of the system and add functionality to your smart home.

2. Amazon Alexa Integration

The Ecobee3 connects to the Amazon voice control devices (such as Echo and Dot), so you can connect your smart home to your smart thermostat via Alexa commands.

The Ecobee4 takes this one step further by adding the Echo directly into the thermostat. They have included a microphone and speaker to the thermostat which allows you to speak directly to the Ecobee4 using Alexa voice commands.

There are a few limits to the integration, such as the inability to order on Amazon, use third-party apps such as Spotify, send or receive messages or rename the call action (rename “Alexa”).

Once the thermostat is installed and you add the Ecobee thermostat through the mobile app as an Alexa-enabled device, you can fully control your home heating and cooling system with just your voice.

One add-on that you may find distracting is the giant blue LED light on the top of the Ecobee4. This light tells you that Alexa is enabled and ready. You can use the app of the voice control menu on the thermostat to disable the feature. When you do, the light will turn red.

As of this writing, there is no way to turn the light off completely. I do hope that Ecobee fixes this, but I haven’t been able to find any evidence they are going to.

The Alexa integration is a bit confusing, to clarify:

Both the 3 and 4 are WiFi connected, and both can be controlled by voice through an Amazon echo device.

The ecobee3 does not have Alexa built in. If you don't use an Amazon echo device, you cannot control it by voice.

The ecobee4 does have Alexa built in. You do not need a separate Amazon device to control it by voice. 

The Alexa built into the ecobee4 is not as advanced as the Alexa on Amazon echo devices, meaning it does not have the full capabilities of an echo device, and is meant for controlling your thermostat only.

Bottom Line: Ecobee4 wins. Building Alexa into the thermostat means you do not have to have an Amazon Echo device nearby to use voice control.

3. Power Extender Kit

The Power Extender Kit (PEK) comes with both thermostats. The PEK is designed to allow installation of the thermostat in homes that do not have the C wire. The C wire is the power supply wire (usually blue) that allows the thermostat to operate.

In older homes, the C wire may not be installed. In this instance, you will need to use the PEK to wire the thermostat to the HVAC control board. I highly recommend you have this installation done by a professional. It is a dangerous install because of the voltage involved, and you can cause damage to the thermostat, the HVAC unit or yourself.

You cannot use the PEK from an existing Ecobee3 system if you upgrade to the Ecobee4. The terminals have been moved in the Ecobee4, and you will need to use the PEK that comes with it.

Bottom Line: A tie. The PEK is included with both models, allowing you to have either smart thermostat installed regardless of your C-wire situation.

4. Far Field Voice Recognition

New to the Ecobee4 is the inclusion of the Echo inside the thermostat. To utilize this, Ecobee has included Far Field Voice Recognition. This allows you to be some distance from your thermostat and still be able to use the voice functions.

One major drawback I noticed with this is that the voice recognition will also pick up your television. So on the off chance, an Amazon Echo commercial comes on, it may activate the thermostat.

Another drawback is that even though the name states it is far field, this is very subjective. Most people, myself included, have the thermostat installed in a hallway. The living room (as is the case in my house) is too far away to pick up my commands.

However, if you already have an Echo or Dot, you can use those to communicate to the thermostat as well. If you do not, it may be something to consider purchasing to get full optimization from the Ecobee4.

Bottom Line: Ecobee4 wins, it’s the only device here with Alexa built in. Far Field Recognition is just a feature of that technology.”

5. LCD Touch Screen

Both the Ecobee3 and the Ecobee4 have near identical 3.5-inch touchscreens. The only difference is the inclusion of the voice control button on the Ecobee4.

This is included to allow menu control of the Alexa component of the Ecobee4. From this, you can enable or disable the Alexa control (changing the top lit LED from blue to red) adjust volume controls for the speaker, turn the microphone on or off, and manually force Alexa to listen to you over ambient or background noises.

All other features of the touch screen and their controls are identical in the two units.

Bottom Line: The Ecobee 4 has the voice control button, but the Ecobee 3 does not. Otherwise the LCD touch screens are the same.

6. Humidifier, Dehumidifier, Ventilator Support

The Ecobee3 gave full support to the HVAC system and components. The Ecobee4 carries this over as well.

If your HVAC system has humidifier or dehumidifier components, they smart thermostats will be able to control them as well. This is also true for ventilators and even dual fan systems, and HRV and ERV exhaust components.

The functionality and installation are the same and should still be just as easy in the Ecobee4 as it was in the Ecobee3. Just make sure, if you are upgrading from an Ecobee3, you note any wire terminal changes that have occurred with the Ecobee4 release.

Bottom Line: Both Ecobee thermostats will control virtually every HVAC component you may have installed.

Frequently Asked Questions

With all technology, there will be questions you want to be answered before making that final purchase. I have gathered the most important and often asked ones here and will attempt to answer them for you.


Q: I have an Ecobee3 and want the Ecobee4, will my room sensors work with the Ecobee4?

Yes, they will. But before they do you have to cast a magic spell on them. It’s really easy though:

Step one, install the Ecobee4. Step two, remove the batteries from the room sensors, step three, reinstall the batteries. Step four, confirm on the panel you want to connect the sensors. (Magic words and ritual dances optional.)

Q: Will the Ecobee3 or Ecobee4 work with Wink?

Currently, Ecobee thermostats work with Amazon Alexa, Google Home, IFTTT, Samsung, and Apple. They do not have Wink compatibility as of this writing. However, the head honchos at Ecobee say they are working on it and should release an update soon.

Ironically, the Ecobee thermostats work with Samsung SmartThings hub, which has a Wink relay. I have not been able to test it, but it seems logical that it should work.

Q: Does Ecobee have geofencing?

Yes, the ecobee has been updated to include this function, allowing your smartphone to sense when you are home vs when you are away from home and tell the thermostat to enter the appropriate scene. For more details on this feature, see ecobee’s article on geofencing or watch the video below.

Q: I use Hue lights, which tell me they need an Alexa hub, with the Ecobee4 act as this hub?

Yes and No. You can speak to the Ecobee4 to control smart lighting (such as HUE) with its built in Alexa.

However, you have to have a separate standalone Alexa device such as an Echo or a Dot for Ecobee4 to talk to the cloud. The thermostat itself cannot BE the hub but will relay voice controls to the hub once it is learned in.

Q: Can ecobee work without wifi?

Yes, but you probably wouldn’t want to.

You can still set up and use both the ecobee3 and ecobee4 without a WiFi connection. It will just work as a traditional, non-smart thermostat. However, you won’t be able to use most features of a smart thermostat such as the ability to control the temperature while away from home.

If you don’t have WiFi at home, there is no need to get a smart thermostat. Save money and get a traditional thermostat instead.

Q: Can I use an Ecobee 3 or Ecobee4 in my RV?

Probably not, but it is not impossible. The Ecobee3 and Ecobee4 are 24 volt systems using the common wiring of Red, Cyan, Green, Yellow, White. Most RVs are 12 volt systems. If you are running a 12-volt system in your RV, then the Ecobee thermostats will not be compatible.

If you are running a 24 volt RV and have ensured you have the correct five wire system, then it should work just fine.

Q: Will the control app work on my tablet?

Yes. Tablet, cell phone or any device you can use apps for either Android or iOS.

The app will work on any mobile device, even Fire tablets, so long as you have connectivity to the home network.

Q: I need to change the wake name of the thermostat, my dog’s name is Alexa, and we keep waking up the thermostat.

Unfortunately, you cannot change the wake name from Alexa on the Ecobee4 thermostat. For some unknown reason that was one of the features that were disabled on the Alexa-enabled Ecobee4.

Other features were also disabled such as sending and receiving messages and playing a lot of third-party apps.

At this point, it would probably be better to rename your dog.

Q: Does the thermostat have a sensor for the floor it’s installed in or do I need a separate room sensor?

The thermostat has a sensor built in to the front face. This is a full sensor for temperature as well as motion (if you choose to utilize the Home and Away mode or the Follow Me mode). It is not required to have a separate room sensor for the thermostat.

If you do purchase extra room sensors (remembering that you will get one free with each Ecobee3 and Ecobee4 thermostat) you need to keep in mind they have a limited radius from the thermostat to work correctly. Last test was about 45 feet.

Q: Can I have different sensors used for separate thermostats?

Yes you can. When you install the thermostats, say you have dual zones, you can then add your room sensors to those thermostats.

Once the room sensor is powered on, the signal will be picked up at the thermostat and asked if you would like to include it. If both thermostats pick up the sensor, you only need to sync it to the thermostat you wish to use that sensor for.

It will no longer be available for the other thermostat, thus enabling you to run everything as intended.

In Conclusion

If you are after total home automation, want full voice control over your entire HVAC system and wouldn’t mind getting recipes read to you and hearing the current weather from your kitchen, then the Ecobee4 is the smart thermostat for you.

With a few minor aesthetic upgrades and Alexa built right in, you can connect your thermostat to your smart home simply and quickly.

However, if you are on a budget, or don’t have the need for another Alexa-enabled device, the Ecobee3 is still the best option for smart thermostat installation.

Both the Ecobee3 and Ecobee4 are identical in their features and abilities, with the main exception being the integration of Alexa in the Ecobee4.

You can achieve the same functionality (without the loss of abilities) by purchasing the Ecobee3 and an Amazon Echo or Dot. However, with the integration and ability to link Alexa-enabled devices, the smarter choice is to go with the Ecobee4.

Check here to see all the smart thermostat deals on Amazon today. 

15 thoughts on “Ecobee3 vs Ecobee4 – Everything You Need to Know”

  1. Thanks for the cogent comparison.

    You do know that the “save 23% on energy” isn’t the energy used by the thermostat, don’t you? With or without the power extender kit the thermostat is going to draw approximately the same power from your HVAC system. The extender just provides a way to get that power to the thermostat.

    The energy savings is gained by performing a “setback” functions to lower temperature in the winter when you are away or at night compared to a dumb fixed temperature thermostat. Setback thermostats have been available for more than 35 years so this isn’t a new concept but it is definitely new packaging and easier than ever control with the Ecobee.

    1. Hi Phil,

      I have reworded the section on the power extender kit to reflect that the PEK does not affect the energy savings.

      Thank you for your kind words and awesome clarification!

  2. Hi,
    Great review, and actually is steering me towards the Ecoobee3. My house is set up like your, where my thermostat is in the hallway and unless I want to stand in the hallway to talk to my thermostat having the the built in Alexa, is a waste.

    The one thing that is confusing about your review is the Bottom Line for #5. LCD Touch Screen. It sounds like you are saying the 3 does not have a touch screen, but the 4 does, and I think you mean the 3 does not have the voice control button.

    1. Hi Scott,

      The way that sentence is worded is confusing and I have fixed it. Thank you for pointing this out! You’re awesome.

  3. If I am reading right, you can control the 3 by voice but it does not answer questions like What is the weather because it is not connected to the cloud? Or what does it mean being connected to the cloud? I appreciate your review of the products.

    1. Hi Kim,

      Good question, I apologize for not being more clear. I have added to the article, please look for the grey box under “Amazon Alexa Integration” for the clarification.

  4. Kevin,

    Great review, the one thing that is misleading is the fact you say you can control all your HVAC needs, is a little deceiving. The fact is there is only one set of ACC contacts. That leaves you with only one accessary that you can control. So if you want set your system to Dehumidify in the summer and control your Humidifier in the winter, you must reconfigure, and rewire for each season.
    That is the one downfall of this stat. They’re original Smart Stat, that came out in 2009, was they’re best one, it had all the bells and whistles.
    I am waiting for them to upgrade this one before I upgrade mine.
    Fantastic product and excellent quality control.

    Thanks for the review

    1. Thank you for your insightful comment Jim. I am sure readers who have humidifiers in addition to their AC units will appreciate your advice!

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