Ecobee4 VS Ecobee3 VS Ecobee3 Lite: What’s The Difference Between The Three?

In 2014, Canadian smart home company, Ecobee, has released a well-acclaimed smart thermostat called Ecobee3 and which was met with much praise. Often compared to Nest Smart Thermostats, Ecobee3 won tons of followers.

Then, three years after releasing Ecobee3, the Ecobee4 and  Ecobee3 Lite were born. While Ecobee4’s main selling point was Alexa integration, the Ecobee3 Lite promised to be a cheaper alternative with fewer features. So now with all 3 products on the market at the same time, what is the real difference between these products?

In this post I will try to explain the key differences:

Physical Appearance

The Ecobee3 and Ecobee3 Lite ALMOST look the same, with only minor differences.

At a glance, they both have a sleek, glossy black plastic, modern design. It’s simple and very minimalist. They are both square-shaped gadgets with rounded corners (the Lite version having slightly more rounded corners).

The Ecobee3 has dimensions of 4x4x0.9  inches, while the Lite version is a bit smaller at 4x4x0.8 inches. Both have a 3.5-inch QVGA touchscreen at the center of the device. The Ecobee4 is slightly thicker at 4x4x1 inches.

At the lower left corner, you can see a wedge-shaped section, which is the motion sensor. It might be harder for you to see the sensor in the Lite version, though, as it protrudes less than that of the classic Ecobee3.

Overall, the design in all of them is very minimalist and the screen display very simple and easy to understand.

The Ecobee4  is slightly different, as it has a blue led bar on top of the display that lights up when Alexa is activated.

Compatibility with HVAC Devices

This is one of the key differences between the two thermostats. The Ecobee3 is compatible with a wide range of HVAC devices. It supports heat pumps, electric systems, gas systems, oil systems, as well as ventilators, humidifiers, dehumidifiers, energy recovery ventilators (ERV), and heat recovery ventilators (HRV).

The same cannot be said for the Lite version though. It is not compatible with humidifiers, dehumidifiers, and any kind of ventilators. So if you have a home with these HVAC appliances, you might want to consider the classic Ecobee3 rather than the Lite version. Otherwise, the Lite might do the trick at a lower price.

Power Source

By default, both of these thermostats are powered by a C-wire, which powers both the display on the thermostat unit as well as its Wi-Fi.

Some smart thermostats like Nest and Honeywell Lyric are operated by built-in batteries, but the Ecobee uses a C-wire as a power source,  making it more reliable and efficient (it doesn’t run out of power). Still, there are some who argue that C-wires are as steady in terms of current.

If you don’t have a C-wire for your thermostat, you can use Power Extender Kit or PEK, that you connect to the furnace control board to draw power from there. You can see this in the video below:


Both, the classic Ecobee3 and the Ecobee3 Lite have the same installation process. It is fairly simple, quick and intuitive thanks to the straightforward touchscreen interface. It is self-explanatory and easy to follow, and the whole set up should not take more than 15 minutes.

The touchscreen shows whether the thermostat is in heating or cooling mode, the current temperature, the target temperature, and several menu options.

Once installed, you will need to create an account on the Ecobee app. That can be done on your phone or the Ecobee website after which you can add HVAC devices to the thermostat’s system.

Once this is done, you can control your thermostat using your phone, or tablet, or computer. You can also set scheduled temperatures throughout the day, along with many other functions. We will talk more about these functions later.

Room Sensors

This feature is one of the things that makes the Ecobee really stand out from other smart thermostat brands. Room sensors are wireless remote sensors you can place in different rooms in your house. This way, the thermostat can detect the temperatures in other rooms and regulate them accordingly.

The room sensors don’t need an app to set them up, and they link directly to the main thermostat unit. You just place them in different rooms around the house and pretty much forget all about them.

Room Sensors as Motion Detectors

But that’s not all these room sensors do – they also detect movement! They can monitor whether or not someone is at home or has just entered the room. It is all done with the “Follow Me” function. When it is turned on, the thermostat activates the AC or heater only when you are actually in the room, which is great.

Ecobee claims that their smart thermostats save up to 23% on energy consumption.

Now, it would be great if you could control the temperature for each room independently. The Ecobee3 and its Lite version come pretty close to doing that (with the help of their room sensors). However, as these thermostats try to achieve consistent temperatures throughout the house, they might create inconsistencies. For example, if the bedroom is too cold, the thermostat is trying to even out the temperature with the living room and the room could get too hot. This may be one of the downsides of Ecobee thermostats.

Each thermostat unit supports up to 32 sensors, more than enough for a medium-size house. Just keep in mind that they should not be more than 45 feet (a little less than 14 meters) away from the main unit or they will not be detected by the thermostat. The room sensors are wireless and powered by 3 Volt CR-2032 batteries, which should last for about 4 years.

The main difference between the classic Ecobee3 and the Lite version is that the Ecobee3 Lite box does not include the actual room sensors. For the classic version, you get one sensor in the package, while the Lite version has none. However, they still support the sensors.

Home/Away Setting and Geo Fencing

Both the classic Ecobee3 and the Ecobee3 Lite have a setting called Home/Away. If activated, you can set a temperature for both when you are at home and when you are not. When you get home and the motion sensors detect your presence, the home setting overrides the away setting and immediately implements it.

The geofencing feature allows the Ecobee3 thermostat to track your phone’s location. When it detects that you are approaching home, it automatically engages the home setting or whatever setting is on default.

Sadly, geofencing is not available on the Ecobee3 Lite, but there are ways around that (read below).

Smart Recovery

Another good feature available in all of them, the Ecobee4, Ecobee3 and Ecobee3 Lite, is the Smart Recovery function. What this feature does is consider the current weather conditions and forecasts to determine the best time to heat or cool your house.

With the Smart Recovery setting enabled, you don’t actually have to schedule temperatures anymore, if you are not the type to micromanage. You can simply let your Ecobee do the thinking for you and adjust the temperature based on the weather; the thermostat activates the AC or heater only when you really need it, saving energy.

Main Thermostat Interface

Again, the classic Ecobee3, Ecobee4 and the Lite versions are pretty similar when it comes to the interface. While in the inactive state, they display big white numbers that indicate the current temperature, weather conditions, and the temperature outside.

However, when the motion sensor detects you are nearby, the display changes. The big number in white is still there, indicating the current temperature. But to the right, you will see little dots that form a vertical line which you can use to adjust the temperature setting.

When the main thermostat unit is active, you will see different icons (like weather forecast and Home/Away) on the interface as well as access various settings. You will even see reminders and alerts for HVAC maintenance and repair.

Comprehensive Weather Reporting

One of the things I really like about both these Ecobee thermostats is that they have very comprehensive weather reports. On the display, you can access weather forecasts and schedule temperatures accordingly.

Mobile App and Web Portal

The Ecobee mobile app is available for both iOS and Android. Of course, it is available for both Ecobee3 and Ecobee3 Lite as well.

The user interface for the app is very similar to the interface of the main thermostat. If you use your computer to access the site, you will have ready options therwise accessible through different icons in the app and the main thermostat interface.

The main thermostat’s response to commands using the app or the web portal is fairly quick and seamless, but it depends on the strength of your WiFi connection.

Data Tracking

Both the Ecobee3 classic and Lite versions keep track of changes in temperature settings. However, this data is only available in the web portal and not in the main thermostat’s interface, nor on the mobile app.  Some people do not like that, but I think it helps to keep the thermostat screens clutter free and simple.

So what kind of data can you access through the Ecobee website? Here, you can access records of implemented changes in the temperature, the adjustments made, even energy consumption. The data is encrypted so there’s no need to worry about safety here. The only downside to the tracking feature is that the Ecobee will only start tracking this data after a whole month of usage.

Connectivity With Smart Home Hubs/Devices And Services

All 3 products — the classic Ecobee3 and the Ecobee3 Lite and Ecobee4 — can connect to smart home hubs and devices. This includes Apple’s Homekit, Amazon Echo, Samsung’s SmartThings, Control4, and Vera Smart Home Systems. For some of these hubs, like Homekit, Amazon Echo, and others, you can incorporate your Ecobee thermostat and group it with other smart home devices and appliances. This enables you to activate or deactivate them all at once.

Also, you can take it to the next level and make your Ecobee thermostat voice-activated with Siri (Apple Homekit) or Alexa (Amazon Echo). The Ecobee4 comes with Alexa already integrated.

What’s more, you can integrate IFTTT (If This Then That for all you smart home newbies out there) with all 3 thermostat models and turn it on whenever you get home or inactivate it automatically when you leave. I love this as it can be used as a workaround to Ecobee3 Lite’s lack of a geofencing feature.

Apple Homekit Integration

When you plan to connect an Ecobee3, Ecobee4 or Ecobee3 Lite to the Apple Homekit, make sure you have the updated and compatible version of the product. It should have a Homekit logo on the package or a number EB-STATe3-02 or EB-STATe3c-02 at the left corner on the back.

So, what are the benefits?

  • You can control it via different Apple devices using Siri, iPhone, iPad, or even an Apple Watch.
  • Easy installation. When the mobile app detects the thermostat, it appears on the phone and a pairing code shows on the main thermostat’s interface. You will have to insert that code into the app to pair the two devices.

There are some downsides, however:

  • The feature that allows automatic switching between cooling and heating is not available.
  • It is more expensive than the classic Ecobee3, Ecobee4 or Ecobee3 Lite.

In Summary

What is the Difference Between Ecobee3 and Ecobee3 Lite?

The only real difference between these 2 products is their compatibility with HVAC devices. The Ecobee3 Lite does not support as many and it does not come with geofencing capability and a room sensor in the package.

What is the Difference Between the Ecobee3 and Ecobee4?

The main difference between the Ecobee3 and Ecobee4 is Alexa integration. The Ecobee4 also has better sensors and a LED light bar on the display: all other features are pretty much the same.

What is the Difference Between the Ecobee3 Lite and Ecobee4?

The Ecobee3 Lite was designed as a cheaper alternative with fewer options than the Ecobee4. The Ecobee3 Lite does not support as many HVAC devices, does not come with Alexa integration and the sensors are not as good. The Ecobee3 Lite is designed with smaller homes in mind and for the more price-conscious customer.

To summarize the similarities and the differences between the classic Ecobee3 and the Ecobee3 Lite, please read this table.

Differences Between Ecobee4, Ecobee3 and Ecobee3 Lite

Feature Ecobee4 Ecobee3 Ecobee3 Lite
Dimensions 4x4x1 4x4x0.9 4x4x0.8
Compatible HVAC devices Heat pumps, electric systems, gas systems, oil systems, ventilators, humidifiers, and dehumidifiers Heat pumps, electric systems, gas systems, oil systems, ventilators, humidifiers, and dehumidifiers Lacks terminals for ventilators, humidifiers, and dehumidifiers
C-Wire and Power Extender kit Available YES YES YES
Compatible with Mobile App YES YES YES
Can support room sensors YES YES YES
Included Room Sensor in Package YES YES NO
Geofencing Capability YES YES NO
Weather Forecasts YES YES YES
Smart Recovery YES YES YES
Data Tracking YES YES YES
Compatible with Smart Hubs and IFTTT YES YES YES
Alex Integration YES NO NO
Audio & Voice Recognition YES NO NO
Sensing Abilities HIGH AVERAGE LOW

Which One is the Best Option for You?

As I said at the start of this article, there is really no better or worse here; they are simply a little different. All in all, I would say that if you don’t have that much space and don’t have humidifiers, dehumidifiers, and ventilators at home, the Lite version is the better choice simply because it is cheaper.

However, if you have many rooms in your house that need monitoring, and you have multiple HVAC devices, the Ecobee3 is a better option. And if you want to use Alexa in your house, you should get the Ecobee4.