Comparison Vaillant sensoCOMFORT VRC 720 f vs Vaillant eRELAX

The type of equipment for which the regulator is suitable.

Modern thermostats and automation systems can be used for:

- For different types of boilers — gas, electric, solid fuel.
- For heaters and underfloor heating - for both at the same time: the control features in both cases are very similar, which makes it easy to combine them in one device.
- For pumps — namely for circulation pumps of heating systems.
— For heat pumps. A heat pump provides heat transfer from the environment to the room, providing heating. (Air conditioners work on a similar principle, but their main task is cooling).
— For fancoils. A fancoil is a device that cools or heats air by passing it through a system of pipes with a coolant circulating through them. And for the necessary heating or cooling of the coolant, another component of the system is responsible - a chiller, usually installed outdoors. A feature of such climate systems is that most of them can be used not only for heating in the cold season but also for cooling in the hot season.
— For outdoor system. Regulators for various climatic equipment installed outdoors. These can be, for example, anti-icing systems, devices f...or heating pipelines, chillers for chiller-fan coil systems, etc.

In many models, several options are combined at once; for example, most devices for electric boilers are quite compatible with gas boilers.

In any case, it is the first criterion that one should pay attention to when choosing.

The way to install the thermostat.

— Into mounting box. Installation in a standard junction box. Simply put, the regulator is mounted into the wall in the manner of a conventional switch or socket (most often even the mounting dimensions are the same, although there are exceptions). For installation, most likely, you will have to work with a rotary hammer, but the device will be securely fixed and at the same time will take up a minimum of space.

— On wall. These thermostats usually have a flat shape with a small thickness. Wall mounting is easier than embedding, but somewhat less reliable — in case of an unfortunate set of circumstances, the device can be hit and seriously damaged.

— To boiler. Installing a thermostat directly on the boiler. This option is traditional for devices used in solid fuel boilers (see "Type") that control combustion through a chain connected to an air damper, but it can also be found in other types of regulators — for example, designed for gas boilers. In the first case, this method of installation is due to the design features of the device (see "Chain length"). In the second case, installation on the boiler simplifies the design and installation, but at the same time makes the regulator not very convenient: on the one hand, the design does not have a remote unit, the connection of which is associated with certa...in troubles, on the other hand, you will have to approach each time to adjust the thermostat. to the boiler, which is not always convenient.

— DIN rail. Mounting on a special metal rail, which can also be used for electrical grounding. Such rails are commonly used in distribution boards. Most often, this installation method is used in industrial equipment, although it can also be useful for residential premises. Note that there are several types and sizes of DIN rails. Therefore, before buying a regulator with such an installation, it is highly desirable to clarify its compatibility with the seat.

— Portable. Devices that do not require permanent installation in the same place. By definition, they use a wireless connection (see above). Most often, portable thermostats are equipped with stands for installation on a table or other flat surfaces and are designed more for desktop use than for the role of a portable remote control. Nevertheless, the design makes it easy to move such a device from place to place, which can be useful, for example, in a large house, where you have to be in different places at different times and it would be inconvenient to run to the wall or built-in thermostat every time. Among the disadvantages of portable thermostats, one can mention the rather high cost and the need to use a battery (respectively, a limited operating time).

— In socket. Thermostats plugged into a regular household outlet. Usually, such devices have their own socket on the case and play the role of an adapter switch through which an electric heater (or other device) is connected to the network. With this connection, the thermostat controls the power coming from the outlet: turns it off when the required temperature is reached and turns it on when necessary. Such devices are extremely easy to install. Moreover, they are easily rearranged from outlet to outlet. On the other hand, the very location of the thermostat is not very convenient — sockets are often located in hard-to-reach and not the best places for a temperature sensor.

It is the range in which the air temperature can be set on the regulator. The choice for this indicator depends on the expected conditions in the room. So, in a residential building, the lower temperature limit at the level of 5–10 °C is quite sufficient; the upper limit is within 30–40 °C (regardless of whether we are talking about air or floor temperature). But in control devices designed for industrial use, this range will be much wider — from sub-zero temperatures to the upper limit of 100 – 125 °C.

The presence of an air temperature sensor in the design or delivery set of the controller — such a sensor can be either built into the device or external.

Air temperature is one of the key parameters that determine the climate in the room and the comfort of staying in it. Accordingly, the air temperature sensor allows the regulator to evaluate the general conditions in the room and control the heating operation, taking into account how the microclimate corresponds to the desired one. However, note that such sensors are not always applicable. For example, in kitchens and bathrooms, they may not work correctly (when hot water, a gas stove or a water heater is turned on, etc.), so in such conditions it is better to use floor temperature sensors (see below).

Features of an outdoor temperature sensor used with a thermostat.

Such a sensor, as the name suggests, monitors the outdoor temperature and provides additional information that contributes to the accurate and efficient operation of the automation. For example, with a significant cold outside, the heating system can turn on in advance, without waiting for the room to become colder and this will be recorded by the internal sensor. It avoids unnecessary temperature fluctuations and increases the overall efficiency of the system.

Thermostats that allow outdoor temp sensor connection may initially have such a sensor in the kit, or optionally supplied with it (in this case, the presence of the sensor should be specified separately and, if necessary, ordered additionally). These details are specified in this paragraph.

The maximum communication range between the receiver and the transmitter of the wireless thermostat (see "Connection"), ensured when operating indoors.

There are walls between the thermostat and the remote unit that impede the passage of the signal. Therefore, the communication range indoors will inevitably be less than outdoors (see below). It is also worth noting that this parameter is indicated based on a certain average number and thickness of walls. In fact, in some cases (in particular, if the walls are thick), the communication range can be noticeably less. Therefore, it is worth choosing according to this parameter with a significant margin. Nevertheless, it is quite possible to compare different models with each other in terms of the communication range indoors.

The maximum communication range between the receiver and transmitter of the wireless thermostat (see "Connection"), ensured when working outdoors — or in any other situation when the units are in direct line of sight from each other and there are no obstacles in the signal path. It is the maximum possible theoretical communication range provided by the device. The receiver and transmitter are rarely installed in line of sight, so this parameter is mainly for a rough estimation of communication capabilities and comparison with other models.

The largest number of individual cycles that the thermostat timer can set in one day.

The cycle is the period during which the thermostat operates on one set of settings. For example, if there are 2 cycles, you can provide turning off the heating while you are at work and turn it on shortly before returning home. However, most thermostats provide a noticeably larger number of cycles — up to 24.

Note that in weekly timers (see "Timer type") this parameter may differ depending on the day of the week. For example, weekdays usually have more extensive settings than weekends.

— Display. The presence of its own screen in the design of the regulator. Such a screen is usually a simple LCD matrix with segment digits. However, even on such a screen, very diverse data can be displayed (including temperature with an accuracy of fractions of a degree), and this function significantly expands the capabilities of the thermostat and makes it more convenient. Note that it makes sense to install the display primarily in electronic models (see "Device type"), for such thermostats it is almost mandatory (but in mechanical ones, on the contrary, it is almost never used).

— Protection of the pump from "souring". During non-working hours — for example, between heating seasons — deposits can form on the parts of the circulation pump of the heating system, which can make it difficult to rotate the impeller, reduce the efficiency of the pump, or even disable it altogether. This phenomenon is called "souring". To avoid it, automatic regulators may provide protection against acidification: periodically (once every few weeks) the pump is turned on for a short time, which prevents the formation of deposits (and removes those that have already formed).

— Holiday function. A special regime provided for in case of a long absence of people in the house (for example, during a vacation — hence the name). In holiday mode, you can set a certain temperature to...be maintained for several days (for example, a week; the maximum duration depends on the thermostat model). At the same time, in some models, this function is combined with frost protection (see below) and allows you to set only the minimum temperature (usually 5 °C); in others, the holiday temperature can be programmed.

— Random mode. A mode that provides for the inclusion of various heating functions in a random order (but without causing critical loads on the heating system). The most popular use of this feature is to simulate that someone is at home; this can stop intruders planning a theft in the absence of the owners.

— Management via the Internet. Ability to control the controller via the Internet. The device itself is usually connected to the network via Wi-Fi, and the control features may be different. For example, in some models you need to use a proprietary application installed on a smartphone or tablet, in others it is enough to open a special page in any browser. However, anyway, this function allows you to control the heating system remotely, from anywhere in the world. This can be extremely convenient in unforeseen situations — for example, if during the absence of the owner on the street it gets warmer. In addition, additional features such as advanced timer programming may be available with Internet control.

— Frost protection. A function that prevents freezing of the coolant in heating systems. Freezing water expands, which can lead to mechanical damage and depressurization of the system. To avoid this, regulators with this function are able to "monitor" that the temperature of the coolant does not fall below 5 °C, and, if necessary, turn on the heating to maintain the temperature. This function is relevant primarily for cases when the disconnected heating system must be left unattended for a long time during the cold season.

— Protection from children (blocking). The ability to lock the control panel of the regulator so that a curious little child cannot knock down its settings. The lock, usually, is turned on and off in such a way that an adult, but not a child, can easily do it — for example, by simultaneously pressing certain keys.

— Heater operating hours counter. Built-in counter that tracks the total heating time. This feature makes it much easier to keep track of the operating mode and heat costs, eliminating the need for the user to keep records manually and allowing you to track working hours even when there is no one nearby.

— Sensor calibration t. Possibility to calibrate the temperature sensor of the thermostat. In fact, situations may arise when the readings of the temperature sensor for one reason or another differ from the actual temperature in the room — for example, the controller is installed near an electrical appliance that generates heat and knocks down the setting, and neither device can be moved. For such cases, calibration is provided — an amendment to the readings of the temperature sensor. For example, if the thermometer in the middle of the room reads 20°C and the regulator's sensor reads 22°C, you can correct the thermostat to -2°C and the temperature displayed on the regulator will correspond to the true temperature. Of course, the correction can also be taken "in the mind" without reconfiguring the device; however, most often it is easier to set the necessary parameters in advance and not get confused in the calculations.