In this article I will review the smart radiator thermostat V3+ from tado° and have tested it in combination with the Alexa voice control. The version V3+ is the latest version of tado° and is also compatible with older tado° thermostats. The thermostats are suitable for new buildings but also for retrofitting in existing buildings.
This article is part of my article series Reviews of Intelligent Heating Control Systems, in which I test and review systems from different manufacturers. The components were provided to me by tado° for reviewing, thank you very much.
Last updated prices on 2021-09-17 / Picture source: Amazon affiliate program
Table of Contents
- 1 The main features
- 2 Components of tado° heating control
- 3 Components of the tado° heating control
- 4 Installation of the tado° Starter Kit V3+
- 5 Installation of the tado° App
- 6 The tado° App
- 7 Integration of tado° into Alexa voice control
- 8 Usability
- 9 Control behaviour
- 10 Conclusion
- 11 Review rating
- 12 Starter Kit - tado° Smart Radiator Thermostat V3+
- 13 Pros
- 14 Cons
The main features
First of all, you naturally ask yourself why you should buy an intelligent heating control system like the one from tado°. The primary goal is to increase comfort through such a system, to control the heating according to demand and thereby reduce energy consumption and thus operating costs. According to tado° the energy savings can be up to 31%.
The tado° radiator thermostat V3+ is the third thermostat version of tado° and, according to the company, has improved electronics, which leads to shorter update times and makes the user interface faster. In addition, there are better adapters for Danfoss valves and the thermostats have a temperature sensor as well as a humidity sensor.
Compatibility: If you have an older version of the tado° radiator thermostats, this shouldn’t be a problem. According to tado° they are compatible with the V3+ version (see Compatibility of tado° products). I will go into this later in this review.
What made the tado° system interesting for me is the inclusion of the user’s location (geofencing) to control the heating system. The tado° system can use the location to assess whether someone is at home and decide whether or not heating is necessary. As far as I know, the tado° system is the only one in the field of smart radiator thermostats with this function and therefore has an absolute unique selling point.
The biggest advantage of geofencing is the independent detection of presence and absence, because in other systems the energy saving is achieved by storing schedules for heating times and temperature reduction phases. However, this also means that I have to intervene manually if I’m early in the evening, or it heats up unnecessarily if I’m away outside the defined “heating time”. By using geofencing this is no longer necessary and theoretically you only need to store a time block for the night setback.
Here’s a little hint for Smart Home enthusiasts : tado° is compatible with the voice controls Amazon Alexa* and Google Assistant as well as the software framework Apple Homekit.
Here is a summary of the most important facts about the tado° radiator thermostat V3+:
- Heating costs can be reduced by up to 31%.
- Energy saving guarantee! According to tado° you get your money back in the first 12 months if no energy has been saved.
- Location-dependent control via Geofencing
- Weather Forecast Control
- Control of individual rooms or temperature zones (multi-zone control)
- Statistics on temperature and humidity history, heating activity and energy savings in the tado° app
- Sensors for temperature / humidity
- Data encryption: TLS 1.2 (SSL), 2048-bit Extended Validation Certificate / TLS 1.2 (SSL), 256-bit with elliptical curves / AES-CCM encryption
- Radio link (between the devices): 868 MHz (6LoWPAN)
- works with IFTTT and eNet Smart Home
Components of tado° heating control
For this article, I have tested the following components, which are used in 3 rooms with 4 radiators
Components of the tado° heating control
For this article I have tested the following components, which are used in 3 rooms with 4 radiators
- 2 x tado° Smart radiator thermostats V3+ (current version)
- 2 x tado° Smart radiator thermostats (old version)
- 1 x tado° Internet Bridge V3+ (current version)
Before I start with the test, I will introduce you to the components in more detail:
tado° Smart radiator thermostat V3+
The smart radiator thermostat from tado° looks stylish and has a very high-quality effect. When you unpack it, you immediately notice the missing display on the thermostat and wonder how you can read the temperature on the thermostat.
After activating the battery there is a first “Aha” effect, because the display is not visible at first glance and after activating the battery it lights up with small LED’s on the white surface.
The threaded connection of the thermostat is M30 x 1.5 and therefore fits all common and newer radiator valves. An adapter set for Danfoss RA, RAV and RAVL valves is included.
In addition, there are two batteries in the thermostat, which must be activated by pulling a small tab. Otherwise a user manual and a QR Code for pairing the thermostat with the Internet Bridge are included in the package. The thermostat is available for purchase on Amazon:
Last updated prices on 2021-09-15 / Picture source: Amazon affiliate program
tado° Internet Bridge in Starter Kit V3+
The Internet Bridge for the tado° system is not available for purchase separately, but is included as standard in all Starter Kits and is necessary for connecting all tado° components. The communication of the tado° components with the Internet Bridge is done by building an “Ultra Low Power” wireless network.
The range of the Internet Bridge depends largely on the structural characteristics of the building, but can be up to 20 meters. The tado° radiator thermostat Starter Kit V3+ is available on Amazon:
Last updated prices on 2021-09-15 / Picture source: Amazon affiliate program
Installation of the tado° Starter Kit V3+
After unpacking the tado° components you can start with the installation. In figure 6 I have shown all components again. For the test, two Smart radiator thermostats are installed in the living room, one in the kitchen and one in the bathroom. The Internet Bridge is located in the living room. So 3 rooms with a total of 4 radiators are controlled. The distribution is as follows:
- Living room: 2 smart radiator thermostats, 1 internet bridge
- Kitchen: 1 smart radiator thermostat
- Bathroom: 1 smart radiator thermostat
Installation of the tado° App
Before you can start installing the components, you have to download the app from tado° in the respective App Store. The app is available for free download for Android and Apple devices. Once the tado° app has been installed, you will need to open a user account as shown in the following pictures and enter the necessary data to continue with the installation.
Alternatively, a user account can be created via the web interface of tado° at my.tado.com However, I recommend the app, because it is much easier to connect the components to the Internet Bridge.
Installation of the Internet Bridge V3+ from tado°
Once the app is installed we can start with the installation of the tado° Internet Bridge. First I connected the Micro USB cable, which is very short, and the network cable to the Internet Bridge.
Then I plugged the network cable into my router and the USB cable with USB power supply into an electrical outlet. Now the Internet Bridge can be connected to the app.
Note: Since the included Micro USB cable is very short, the power outlet must be very close to the router or you will have to get a longer Micro USB cable (e.g. 3m)*.
In the overview of the app (Home) you then press “Add new device” and then “smart radiator thermostat”. Now you are asked to install the Internet Bridge, which we will do. To do this we follow the instructions in the app.
Installation of the smart radiator thermostat V3+ from tado°
Once the Internet Bridge is installed, we can start installing the smart radiator thermostats from tado°. To do this, we select “Add device” in the menu and then “Smart radiator thermostat”. Then we follow the instructions of the app.
To activate the thermostat, the first step is to remove the mounting bracket on the thermostat and pull the battery tab. Afterwards the QR Code will be scanned and the device is registered in the app. By pressing the pairing button, the thermostat is registered in the tado° system.
If the thermostat is successfully registered, it is assigned to a room (e.g. living room) and the device is ready for installation.
In the next step we start with the installation of the tado° thermostat. To do this, we remove the old thermostat and attach the mounting bracket to the valve. The mounting bracket fits valves with the thread dimension M30 x 1.5, which modern radiator valves have as standard. For Danfoss valves adapters are included in the delivery. If you do not know the difference between thermostatic head and radiator valve, I recommend my article “How do Thermostatic Radiator Valves work?“.
Note: Since most old radiator valves have different thread dimensions, adapters often have to be used for modern thermostatic heads to ensure compatibility. In my article “The big overview: Adapters for thermostatic valves” you will find an overview of different adapters as well as installation instructions for a Vaillant (30/30.5 mm) valve.
For careful tightening of the mounting bracket I recommend a water pump pliers*. After the mounting bracket has been mounted correctly, the tado° thermostat can be snapped onto it and calibration can begin. Follow the instructions in the app, as they are very clear and leave no questions unanswered. In figure 10 you can see how the mounting looks like in practice.
If all smart radiator thermostats are installed, we can continue with the settings of the app.
Tip: Here is an overview of the symbols on the tado° radiator thermostats.
The tado° App
When you open the tado° app, the “home screen” appears in tile form. Here you can see all the rooms you have created with their respective set and measured room temperatures as well as other tiles, which I present to you in more detail below. In the lower part of the overview you can switch between “at home”, “settings” and “more”.
tado° App – Area at home
Now we come to the tado° app. In the home area you can make the respective settings for the rooms you have created and see how the current indoor air quality behaves or how much energy you have saved with the tado° system. In the following I show you the overview for the room “living room”.
Overview: If you select the living room, for example, an overview page appears with a display for the currently set room temperature, the measured room temperature and the measured humidity.
Via “smart schedule” you can store schedules with desired room temperatures in the “Home” section. If you have set the geofencing and the app notices that you are not at home, the schedule will be automatically overwritten with the “Away” data (provided you have an Auto Assist subscription) and the temperature will be lowered. You can also activate the option “Easy Start”. This will ensure that the desired room temperature is reached at the beginning of each time block. This applies to “Home” and “Away”.
In the “Away” section you have the possibility to store the setback temperature when the system detects that you are not at home. Furthermore there is the option “Preheat before arrival”. The heating system will then pre-heat the room before you arrive so that the target temperature is reached faster. For this option there are the settings “Off”, “Eco”, “Balance” and “Comfort.
Back on the overview screen, you can view an overview of past temperature histories, humidity values, as well as active heating times and weather data in the top right corner. This overview is perfect for analysing the heating behaviour afterwards and to detect any errors or irregularities.
Air comfort and geofencing
The Fresh air indicator, Outside air and Room air quality areas are displayed in the Air comfort area.
The fresh air indicator shows an overview of the air quality of outside air and indoor air. It indicates, for example, that the indoor air is moderate because no open window has been detected during the last 16 hours. Furthermore, a load forecast should be displayed in case of high pollen load. However, I did not find this, probably because there is no pollen load in winter.
The outdoor air section shows the measured outdoor air values for your particular location. Tado° here refers to the data from Breezometer, which is a pretty cool website by the way. It shows the six main air pollutants: particulate matter, ozone, nitrogen dioxide, carbon monoxide and sulfur dioxide.
In the next area, the indoor air quality of each individual room is displayed. An optimum room climate is achieved when the white point is within the bright circular area. The optimum comfort is determined from room temperature and humidity and is based on the specifications of the ASHARE Standard 55 for indoor air.
For each room in which tado° is installed, detailed information on the room climate is displayed. The comfort status is shown in the top right corner and informs you about the current status together with the white dot in the graphic. Under ideal room air conditions, the white dot is located in the middle of the bright circular area.
In the Geofencing area, only the display shows whether you are at home or not. The radius for the “home” area can be increased or decreased under Settings -> Location-based control -> Home area defined. A radius of 230 m is recommended.
In the energy savings section you can see how much energy you have saved with tado° for the past months.
The total savings are estimated and refer to a conventional thermostat without time control. The savings are divided and determined by the following points:
- Location based control: Number of hours in Away mode.
- Weather Forecast: Number of hours in which the weather had an influence on the heating behaviour.
- Open Window Detection: Displays how many times the temperature of the heating has been lowered by open window detection.
- Smart Schedule: Number of hours your heater has been in a lowered-temperature mode.
- Manual Control: Percentage of time your heater has been manually set to low temperature mode
In the repair service area you can book a repair or maintenance as well as get offers for a new system. This section is only in german available.
tado° App – Settings and more
The “Settings” section of the tado° app is divided into different areas. Here you have an overview of the installed skills. If you click on the respective skills, you will only get hints about the skills and what they can do.
In the “home” area you have an overview of the connected devices, the address data, number of people working with the app and data on heating systems (not relevant for this test).
In the next section, you have the room overview and can specify which thermostat should be used as the leading measuring element. You can also make a temperature correction (in other systems and apps this function is called “offset”).
In the “Notifications” section you can set whether you want to receive a message via smartphone when the battery level is low or the monthly energy saving report is available. Under “More” you have access to support, community, an app beta program, app analysis data and further information.
tado° App – Auto Assist subscription
Before I come to the integration of the voice control, I would like to take a closer look at the Auto Assist function of the app, as it causes me some stomach ache personally.
In the skills overview of the app you will sooner or later come across the item “Auto Assist”, which is inactive by default. It can only be activated by completing a subscription. If the Auto-Assist skill is activated, the energy efficiency settings for “Geofencing” and “Window-Open-Function” will be set automatically.
Without a subscription, you will receive a push message on your smartphone asking if you want to perform an action when a location change or open window is detected (see Figure 11). Without a subscription, you will have to perform many functions manually. The subscription prices are currently €2.99 per month and €24.99 per year (as of January 2020 – see Figure 12). In the section “Usability” I have gone into more detail about the Auto Assist function.
If you want to bypass the subscription and use the software framework Apple HomeKit, you might have a little more luck. As described in the “Digitalzimmer Blog”, the subscription can be partially bypassed with Apple Homekit. Click here for the post: Tado V3+ without subscription – Homekit makes it possible (only in German).
Integration of tado° into Alexa voice control
The first step is to go to Devices in your Alexa App and click on the “Plus Button” in the upper right corner. Then add device, select thermostat and choose the brand tado°.
In the second step you will be asked to activate the tado° skill for Alexa. If this skill is activated successfully, Alexa has to recognize the devices.
The search for new devices takes about 45 seconds. When all devices are recognized and completely set up, you can control your heating with the voice command “Alexa, set living room to 22 degrees”.
For Alexa there are currently the following voice commands that you can use to control tado° (examples):
- “Alexa, turn on living room”
- “Alexa, set the temperature in the bedroom to 23 degrees”
- “Alexa, make it warmer in the basement”
- “Alexa, increase the temperature in the guest room by 3 degrees”
- “Alexa, what’s the temperature in the kitchen?”
- “Alexa, what’s the dining room set to?”
- “Alexa, turn off manual control living room”
- “Alexa, turn on boost living room”
The languages supported are German, English, Italian, Spanish and French.
Let us now come to the usability of the tado° system. I have written down all important factors that came to my mind.
The installation and the pairing processes of the tado° components are very fast and without problems due to the exemplary description in the app. You are intuitively guided through the process, so it is really easy to install the tado° system. When connecting (pairing) the components, however, you will need some patience, as this does not always work immediately. The compatibility with the different versions of the tado° system worked without any problems. tado° really did a very good job in guiding the installation process.
The homepage of the tado° app is clearly arranged and I like it very much. Here you have a first overview with room temperatures and air qualities for the individual rooms and can make or change settings if necessary. Also the section on air comfort is in my opinion very successful and useful.
In my opinion, the energy saving report is a bit confusing and difficult to understand, as it compares the use of a conventional radiator thermostat without time program with the tado° system. According to the tado° energy saving report I saved 15.7% energy in the month of December. But tado° doesn’t know that I had already installed smart radiator thermostats before.
Perhaps it would be useful to set up a selection for the before and after situation, with selection options, whether I had already installed smart thermostats and whether I had, for example, already heated economically before or not. From my point of view the energy saving report can therefore not be used for a real statement, but rather reflects a comparison with a worst case scenario.
Auto Assist function and subscription
I want to talk about the Auto Assist function again, because it really took away the fun of the tado° system.
The Autos Assist function is only active with a paid subscription to tado°. For my review, the Auto Assist function of tado° was activated, so I could test it. However, I have also tested the system for one month without Auto Assist function and I am rather disappointed about it.
With an active subscription, you can sit back and relax and no longer need to worry about the system. It does its job pretty well, just as you would expect from an smart heating control system.
However, an inactive subscription turns the system into a non-smart heating control system and in no way justifies the high price of the system.
This can be seen in the fact that I sometimes read the push messages for taking an action on my phone very late or not at all and my living room was so heated up that I was simply annoyed by the inactive Auto Assist function.
Without a paid subscription, you drive a Ferrari with the handbrake on and the system turns into a “not-smart” heating control system because you have to perform the important actions manually.
From my point of view, the subscription makes the smart radiator thermostats from tado° rather unattractive, because in addition to the high price of the system, running costs are incurred. The subscription prices currently amount to 2.99 €/month or 24.99 €/year (as of January 2020).
Is the paid subscription worthwhile for customers? From my point of view, a clear no. There are many alternative systems which, with the right settings, offer similar comfort, save energy and do not incur running costs.
My recommendation for tado°: Give up the paid subscription function so that everyone can use the Auto Assist function. Then your system is unique and really stands out from the competition.
Function with Alexa voice control
The communication with the voice control Alexa works, but there is room for improvement. What irritated me at the beginning of the test is the permanent change to manual mode when using voice control. This is then active until it is actively terminated by the user. From my point of view it would make more sense to let the manual mode run automatically until the next switching point of the smart schedule, so that the system then switches back to the ” smart” mode.
Background: I had forgotten to switch from manual mode to smart mode (voice command: “Alexa, switch off manual control living room.”) several times and was wondering the next morning or evening why the living room was so warm. In manual mode, the system tried to keep the room temperature permanently high instead of lowering the temperature for the day or night at the next switching point of the smart schedule. Even when absent, the permanently active manual mode overrode the geofencing so that the heating was fully charged when absent. In my opinion, there is room for improvement here.
In this section I will discuss the control behaviour of the tado° components and start with the support of tado°, since not everything worked at first go.
First contact with the tado° support
After the installation I had the feeling for several days that my living room was overheated. The high room temperatures were displayed in the tado° app and also confirmed by a second room thermometer. After close observation I found out that a thermostat in the living room did not sit optimally on a valve (I operate this with a valve adapter). The stuffing box pin of the tado° radiator thermostat seemed to be too short and therefore not able to close the valve completely.
With little hope I contacted the tado° support, which answered immediately. They asked for the serial number of the thermostat in question, which I sent back immediately. The next day I received an e-mail with the following content:
E-Mail tado° Support: “…We have looked at the behaviour and have improved the calibration settings of the affected radiator thermostat(s). Please check within the next 24 hours if this fixes the problem…”
Unbelievable! The tado° support did the calibration of my thermostat remotely, improved it and the thermostat was able to close the valve afterwards. For some people a remote access might be scary, since tado° as a company has direct access to the thermostats. But I found this support ingenious!
My problem was taken care of, analysed and then solved without any kind of effort on my part. So if there are problems with your radiator thermostats, please contact tado° support immediately. They will help you further.
Other control behavior
Otherwise I liked the control behavior of the tado° system in combination with an active Auto Assist subscription very much. The geofencing works flawlessly and the window open detection reacts incredibly good and fast.
Since the window open detection is set to 15 min by default, I recommend extending it to at least 30 min (can be changed under the skill setting). If you forget to close a window, the heating will not start to heat up again until after 30 minutes. This is actually not optimal, because you can heat up when a window is open. This is the first time I have missed window contacts like with other manufacturers. Maybe tado° is planning an extension in this area.
The very quiet setting noises of the tado° radiator thermostats are particularly noticeable. Compared to other smart thermostats, these are hardly noticeable.
The smart radiator thermostat V3+ by tado° is a really good and trend-setting intelligent heating control, which has an absolute unique selling point due to the use of geofencing and thus stands out from the mass of alternative systems.
By using geofencing you don’t have to worry about annoying schedules anymore, but can trust that heating is only done when you are at home (except for the night setback, which in my opinion should be included in the schedule).
Also the window open detection works surprisingly well and better than with alternative systems. Furthermore, the setting noises of the thermostats are hardly noticeable, which is to be emphasized in comparison with other thermostats.
One of the biggest positive features of tado° is the support. It really surprised and convinced me. I had a problem with a thermostat, told the support team about it and they analysed the problem remotely and solved it afterwards. I have never experienced anything like this before. Really great!
Another point I would like to highlight is the simplicity of the installation of the tado° system. Tado° has managed to create an interactive tutorial which includes the active installation. You are guided step by step through the installation process by clear instructions, so that in the end I just thought: “Wow, that was really easy”.
The biggest negative feature of the tado° system in my opinion is the paid subscription to the Auto Assist function. Without the subscription, almost all positive features of the tado° system (geofencing and window open function) are no longer available or only to a limited extent. Instead of an automatic setting, you will receive a push message on your mobile phone and can set the functions manually. The whole thing then has nothing more to do with a “smart heating control”.
A point in need of improvement is the voice control with Amazon Alexa. Switching to manual mode for voice control requires the user to actively exit the mode, otherwise the system will continue to run manually. In my opinion it would make more sense to let the manual mode run automatically until the next switching point of the smart schedule, so that the system then switches back to the “smart” mode.
Update 12/23/2020: Thanks to Jochen who pointed out in the comments section that there are the following alternatives here:
⇨ Until terminated by user (the default variant).
⇨ Until next automatic change (that’s how I set it)
What I also didn’t like so much is the energy saving report in the tado° app, because here the tado° system is compared to the use of a conventional thermostat without a time program. But tado° doesn’t know that I had already installed smart thermostats before. Therefore the impression may arise that I save more energy with tado° than I really do. How much energy I saved in the end will only be shown on the heating bill.
Due to the geofencing function, tado° has an absolute unique selling proposition and from a technological point of view can stand out from other systems. Also the control accuracy and the window open function are very good. If you just look at the technology in combination with the app and the fabulous customer support, tado° would easily climb the throne of smart radiator thermostats.
But what bothers me and makes the system unattractive is the paid subscription for the Auto Assist function. Without the subscription, tado° is not really special and is gambling away a lot of points. If I decide to buy a Smart Home system I don’t want to have any running costs. Maybe I’m a bit old-fashioned here but there are many alternative systems which, with the right settings, offer similar comfort, save energy and do not incur running costs.
Whoever decides on tado° with paid subscription gets the non-plus-ultra for smart radiator thermostats. If you decide against the paid subscription, you get a system which is not really special and comparatively expensive to buy.
Starter Kit - tado° Smart Radiator Thermostat V3+
Scope of delivery9.5/10
Usability/ Control Behavior8.5/10
- Geofencing/ User Location
- Customer Support
- Window Open Detection
- Setting noises of the thermostats very quiet
- Very easy to install
- Subscription service for Auto Assist
- Voice control not optimal
- Energy saving report in the app
Last updated prices on 2021-09-15 / Picture source: Amazon affiliate program
Note: In the set, the components are usually cheaper to purchase than in the individual version. Here is an overview of the offered sets:
Last updated prices on 2021-09-15 / Picture source: Amazon affiliate program
I hope this test report has provided you with some valuable information about the smart V3+ radiator thermostat from tado° and will help you with your purchase decision. If you have any questions, suggestions or criticism, please use the comment function, I look forward to it.
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