A room thermostat is used to control the underfloor heating. It measures how warm or cold it is in the room. It has a temperature sensor for this purpose. The thermostat then transmits the values to the heating system, which adjusts the heating output accordingly. This gives instructions to the actuators that open or close the heating circuits.
To utilize the underfloor heating as efficiently and energy-savingly as possible, the Building Energy Act (GEG) stipulates that the temperature must be controlled on a room-by-room basis. This requirement can be easily met with the smart Shelly components.
The type of control depends on the underfloor heating system installed. For example, it is possible to set the heating output via a manual controller or via the system itself. With Shelly, you don't have to keep running down to the basement or get up and operate all kinds of controllers - you program everything automatically, inform your voice assistant that you're too cold, or use the Shelly app from the comfort of your sofa. We'll tell you what you need.
If you want a central location in your home to control your underfloor heating, the Shelly Wall Display is just what you need. The control panel for your smart home offers a 4-inch screen on which you can not only control the networked scenes and intelligent schedules of your smart devices but also monitor energy consumption. It also shows you the temperature and humidity in the room when it is connected to the Shelly BLU H&T sensor. The display serves both as a control unit for Shelly devices and as a replacement for the conventional room thermostat (RTR).
To be used as a room temperature controller, the Shelly Wall Display requires three connections: L, the conductor that carries the current; N, the neutral conductor, and O, the switched wire to control the heating. The maximum switching load of the device is 5 amps, which is approx. 1,150 watts. It can therefore control both water-based underfloor heating systems with 230 volt actuators and electric heating systems. If you need more than 5 amps, you can combine an additional relay.
If it is not possible to replace the RTR in your underfloor heating system, you can also install another Shelly actuator behind the existing RTR as a switching module - for example the Shelly 1 Gen3, 1PM Gen3 or Pro 1 or 1PM. But more on this later.
The Wall Display works perfectly with the Shelly BLU H&T. The Bluetooth temperature and humidity sensor provides instant environmental data and acts as a smart room thermostat. This allows you to adjust the rules for controlling your underfloor heating even more precisely to the conditions in the room and not only ensure cosy warmth, but also a good indoor climate. After all, correct heating is not only cozy but also prevents damp walls or even mold growth. The small sensor has a battery life of up to three years.
You can also use the measured values from the Shelly BLU H&T without the Wall Display to control the underfloor heating. For example, in combination with the Shelly 1 Gen3. It acts as an actuator for the actuators of a water-based underfloor heating system or controls the operation of the heating mats of an electric underfloor heating system. The BLU H&T then provides the necessary information for smart control. It regulates the control via actions, scenes, or the virtual thermostat in the Shelly app. So if it is too cold in the room, the smart home tells the Shelly 1 Gen3 to turn up the heat output so that you don't get cold feet.
To be used as a room temperature controller, the Shelly Wall Display requires three connections: L, the conductor that carries the current; N, the neutral conductor, and O, the switched wire to control the heating. The maximum switching load of the device is 5 amps, which is approx. 1,150 watts. It can therefore control both water-based underfloor heating systems with 230 volt actuators and electric heating systems. If you need more than 5 amps, you can combine an additional relay.
If it is not possible to replace the RTR in your underfloor heating system, you can also install another Shelly actuator behind the existing RTR as a switching module - for example the Shelly 1 Gen3, 1PM Gen3 or Pro 1 or 1PM. But more on this later.
The Wall Display works perfectly with the Shelly BLU H&T. The Bluetooth temperature and humidity sensor provides instant environmental data and acts as a smart room thermostat. This allows you to adjust the rules for controlling your underfloor heating even more precisely to the conditions in the room and not only ensure cosy warmth, but also a good indoor climate. After all, correct heating is not only cozy but also prevents damp walls or even mold growth. The small sensor has a battery life of up to three years.
You can also use the measured values from the Shelly BLU H&T without the Wall Display to control the underfloor heating. For example, in combination with the Shelly 1 Gen3. It acts as an actuator for the actuators of a water-based underfloor heating system or controls the operation of the heating mats of an electric underfloor heating system. The BLU H&T then provides the necessary information for smart control. It regulates the control via actions, scenes, or the virtual thermostat in the Shelly app. So if it is too cold in the room, the smart home tells the Shelly 1 Gen3 to turn up the heat output so that you don't get cold feet.
In addition to the Shelly 1 Gen3, there are several other smart actuators that can be used to control the underfloor heating. They can be used both in conjunction with a smart room thermostat such as the BLU H&T and with conventional RTRs. Retrofitting smart components for your underfloor heating is therefore no problem. Let's take a look at the various Shelly actuators.
One of the features of the Shelly 1 Gen3 is its so-called potential-free contacts. They are only supplied with voltage by an external power source but do not transmit it themselves. This makes the switch particularly safe and flexible. It can also operate 24-volt DC actuators. It is therefore compatible with numerous new heating systems. It is best to check the technical details of your system or speak to your heating professional. The Shelly 1 Gen3 also supports the installation of an add-on, which makes automation even more versatile.
If the installation of the smart actuator requires a particularly small solution, the Shelly 1 Mini Gen3 is suitable. It can handle a maximum of 8 amps, but offers a particularly compact size and thus enables very space-saving installation - for example behind switches, in flush-mounted boxes, or in the heating circuit distributor. The small switch with WLAN and Bluetooth also scores highly in terms of safety thanks to its potential-free contacts.
The Shelly 1PM Gen3 is a WLAN-controlled smart switch with a maximum switching load of 16 amps. Its range of functions also includes power monitoring. It saves the measured values in the free cloud to optimize power consumption. For example, you can analyze how much electricity your electric underfloor heating consumes. The switch offers a high level of security and also serves as a range extender and Bluetooth gateway for other Shelly devices. You can extend the functionality of the Shelly 1PM Gen3 even further by adding an add-on - for example, a temperature sensor or a humidity meter. You can install the Shelly 1PM Gen3 behind switches, and sockets, in flush-mounted boxes, or directly in the heating circuit manifold.
The Shelly 1PM Mini Gen3 is the right choice for anyone looking for power monitoring in addition to the range of functions offered by the Shelly 1 Mini Gen3. It also offers a switching load of 8 amps and is suitable for use in confined spaces.
The premier class of the Shelly product family is the Pro devices. If you want to install smart switches on top-hat rails in the heating circuit distributor, the sub-distribution, or the main distribution board, the Pro devices are a good choice. They are also worthwhile for controlling the underfloor heating if no WLAN reception is available and LAN cabling is therefore required. In this case, the Pro 1/2, Pro 1PM/2PM, Pro 3, or Pro 4PM are available for controlling your underfloor heating. If these requirements are not met, you can also network your underfloor heating with the classic Shelly components.
The Shelly BLU TRV thermostatic valve is installed directly on the heating system. There it serves as a smart replacement for the analogue radiator or thermostatic valve. Depending on whether the installation location allows it, you can also use it as an actuator for the valves of the underfloor heating circuits. The BLU TRV then receives the commands conveniently via Bluetooth from the Gateway Gen 3 as an exclusive partner and sets the desired heating output accordingly. Incidentally, it is always included in the scope of delivery.
The control of underfloor heating differs from the settings of classic heating systems in several ways. The biggest difference is the inertia of underfloor heating. Due to its design, it is a little more cosy when it comes to bringing a room up to temperature. As it therefore takes longer for the floor to warm up and for the heat to be transferred to the room, it is important to control the system in advance.
For energy efficiency, it is advisable to control different rooms or zones separately, as the heat requirement varies depending on use and location. Anyone who can use a smart control system for underfloor heating is in luck. "Alexa, set the heating in the bathroom to 25 degrees tomorrow at 6 a.m." - a sentence like this is all you need to be greeted with your favorite temperature.
In principle, the heating water in underfloor heating does not need to be as warm as in a radiator, for example. This is because underfloor heating is a surface heating system and therefore distributes the heat more evenly throughout the room.
To control the underfloor heating particularly efficiently and conveniently, the temperature controllers monitor the heat output and automatically send a signal to the actuator when it needs to be warmer or colder. With Shelly, the digital room temperature controllers can then be controlled via the app using a smartphone or wall display. Let's take a closer look at the range of functions here.
To control the underfloor heating, you can conveniently access the free Shelly app. Here you can store your individual schedules, scenes, and comfort temperatures to optimise the heating output to suit your lifestyle. In the app, you network the temperature sensors with the control elements and set the temperature in your bedroom to be a little cooler, while the bathroom could be a few degrees warmer. You can also use the app to control your underfloor heating when you're on the move.
If you opt for the (paid) premium version of the Shelly app, you can use additional services - including weather, additional Alexa skills, dashboards, and much more.
So that the whole family can easily access the heating control, you can operate the temperature control via the Shelly Wall Display. It communicates both with the respective room thermostat and with the smart actuators that control the heating circuits. You can customize the start screen of the Wall Display according to your wishes so that you can directly access your favorites or control device groups with a tap of your finger. You can create a tab for the bedroom to control your bedtime routine. When it's time to hit the hay, the smart home dims the lights, plays relaxing music, and turns down the temperature of your underfloor heating.
There are several ways to save energy with the smart control of your underfloor heating. Let's take a closer look at the most important options.
The individual room control enables efficient control of the underfloor heating. It regulates the flow temperature separately for each room instead of turning the entire heating system up and down. For individual room control, you need temperature sensors and room temperature controllers that control the heating output in each room. This means that only the rooms you use are heated and only at the times when it should be warm. According to the GEG, individual room control is even mandatory - this also applies to retrofitting the heating. Only rooms under six square meters or underfloor heating systems that were installed before 1 February 2022 are exempt.
The room thermostat gives the impulse to open or close the heating circuits to achieve the desired temperature.
No, it should not always run at full power, but it is most efficient when it remains constantly at a low flow temperature. It should be switched off in summer.
Yes, you need a smart room thermostat with a temperature sensor (such as the Shelly BLU H&T), smart actuators (e.g. Shelly 1 Gen3), a smart home center(Shelly Wall Display), and an app.
Yes, with the Shelly app, you can conveniently integrate heating systems into your smart home and automate or control them while you're on the move.
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