Thermostats are small in size, but very practical devices for controlling heat transfer in everyday life. Depending on the actual need, temperature regulators for radiators increase or reduce the volume of coolant. Agree, this is useful both for the well-being of the owners of the house/apartment and for their wallets.

For those wishing to purchase thermostats for equipping radiators, we suggest that you familiarize yourself with detailed description types of heat transfer control devices. We have presented and compared their control methods, operating principles, cost, and installation specifics. Our recommendations will help you choose the optimal variety.

We supplemented the information presented for consideration, collected and systematized for future buyers of heat regulators, with visual photo collections, diagrams, regulatory tables, and videos.

It is known that the temperature in different rooms home cannot be the same. It is also not necessary to constantly support one or another temperature regime.

For example, in the bedroom at night it is necessary to lower the temperature to 17-18 o C. This has a positive effect on sleep and allows you to get rid of headaches.

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The optimal temperature in the kitchen is 19 o C. This is due to the fact that there are a lot of heating equipment in the room, which generates additional heat. If the temperature in the bathroom is below 24-26 o C, then the room will feel damp. Therefore, it is important to ensure high temperature here.

If the house has a children's room, then its temperature range may vary. For a child under one year old, a temperature of 23-24 o C will be required; for older children, 21-22 o C will be sufficient. In other rooms, the temperature can vary from 18 to 22 o C.

A comfortable temperature background is selected depending on the purpose of the room and partly on the time of day

At night, you can lower the air temperature in all rooms. It is not necessary to maintain a high temperature in the home if the house will be empty for some time, as well as during sunny warm days, when some electrical appliances are operating that generate heat, etc.

In these cases, setting the thermostat has a positive effect on the microclimate - the air does not overheat and does not dry out.

The table shows that in living rooms during the cold season the temperature should be 18-23 o C. landing, in the pantry low temperatures are allowed - 12-19 o C

The thermostat solves the following problems:

• allows you to create a certain temperature regime in rooms for different purposes;
• saves boiler life, reduces the amount of consumables for system maintenance (up to 50%);
• It becomes possible to perform an emergency battery shutdown without shutting down the entire riser.

It should be remembered that using a thermostat it is impossible to increase the efficiency of the battery or increase its heat transfer. People with individual system heating. Residents apartment buildings Using a thermostat, they can only regulate the temperature in the room.

Let's figure out what they exist and how to do it right choice equipment.

Types of thermostats and principles of operation

Thermostats are divided into three types:

• mechanical, with manual adjustment of coolant supply;
• electronic controlled by an external temperature sensor;
• semi-electronic, controlled by a thermal head with a bellows device.

The main advantage of mechanical devices is their low cost, ease of operation, clarity and consistency in work. During their operation there is no need to use additional energy sources.

The modification allows you to manually regulate the amount entering the radiator, thereby controlling the heat transfer of the batteries. The device is distinguished by high precision in adjusting the degree of heating.

A significant drawback of the design is that it does not have markings for adjustment, so setting up the unit will have to be done exclusively by experience. We will look at one of the balancing methods below.

The main elements of a mechanical type regulator are a thermostat and a thermostatic valve

A mechanical thermostat consists of the following elements:

• regulator;
• drive;
• bellows filled with gas or liquid;

Electronic thermostats - more complex designs, which is based on a programmable microprocessor. With it, you can set a certain temperature in the room by pressing several buttons on the controller. Some models are multifunctional, suitable for controlling a boiler, pump, or mixer.

The structure and operating principle of an electronic device are practically no different from its mechanical counterpart. Here thermostatic element(bellows) has the shape of a cylinder, its walls are corrugated. It is filled with a substance that reacts to fluctuations in air temperature in the home.

As the temperature rises, the substance expands, resulting in pressure being generated on the walls, which promotes the movement of the rod, which automatically closes the valve. As the stem moves, the conductivity of the valve increases or decreases. If the temperature decreases, the working substance is compressed, as a result the bellows does not stretch, but the valve opens, and vice versa.

Bellows have high strength, long service life, and can withstand hundreds of thousands of compressions over several decades.

The main element of the electronic regulator is a temperature sensor. Its functions include transmitting temperature information environment, as a result of which the system generates the required amount of heat

Electronic thermostats are conventionally divided into:

• Closed thermostats for heating radiators do not have an automatic temperature detection function, so they are adjusted manually. It is possible to adjust the temperature that will be maintained in the room and the permissible temperature fluctuations.
• Open thermostats can be programmed. For example, if the temperature drops by several degrees, the operating mode may change. It is also possible to set the response time of a particular mode and adjust the timer. Such devices are used mainly in industry.

Electronic regulators operate on batteries or a special battery that comes with a charger. Semi-electronic regulators are ideal for domestic purposes. They come with a digital display that shows the room temperature.

The operating principle of semi-electronic devices for adjusting heat transfer by a radiator is borrowed from mechanical models, so its adjustment is carried out manually

Gas-filled and liquid thermostats

When developing a regulator, a substance in a gaseous or liquid state (for example, paraffin) can be used as a thermostatic element. Based on this, devices are divided into gas-filled and liquid.

Paraffin (liquid or gaseous) has the property of expanding under the influence of temperature. As a result, the mass presses on the stem to which the valve is connected. The rod partially blocks the pipe through which the coolant passes. Everything happens automatically

Gas-filled regulators have a long service life (from 20 years). The gaseous substance allows you to more smoothly and accurately regulate the air temperature in your home. The devices come with a sensor that determines the air temperature in the home.

Gas bellows respond faster to fluctuations in room temperature. Liquid ones are distinguished by higher accuracy in transmitting internal pressure to the moving mechanism. When choosing a regulator based on a liquid or gaseous substance, they are guided by the quality and service life of the unit.

Liquid and gas regulators can be of two types:

• with built-in sensor;
• with remote

If the radiator is connected to a working heating system, then the water should be drained from it. This can be done using a ball valve, shut-off valve or any other device that blocks the flow of water from the common riser.

After this, open the battery valve, located in the area where water enters the system, and turn off all taps.

After the water has been removed from the battery, it must be purged to remove air. This can also be done using a Mayevsky crane

The next step is to remove the adapter. Before the procedure, the floor is covered with material that absorbs moisture well (napkins, towels, soft paper, etc.).

A thermometer is placed in the room, then the valve is turned off until it stops. In this position, the coolant will fill the radiator completely, which means that the heat transfer of the device will be maximum. After some time, it is necessary to record the resulting temperature.

Next, you need to turn the head until it stops reverse side. The temperature will begin to drop. When the thermometer shows optimal values ​​for the room, the valve begins to open until the sound of water is heard and sudden heating occurs. In this case, the rotation of the head is stopped, fixing its position.

Conclusions and useful video on the topic

The video clearly shows how to set up a thermostat and implement it into the heating system. As an example, take the Living Eco automatic electronic controller from the Danfoss brand:

You can choose a thermostat based on your own wishes and financial capabilities. For domestic purposes, a mechanical and semi-electronic unit is ideal. Fans of smart technology may prefer functional electronic modifications. It is also possible to install devices without the involvement of specialists.

Installing meters and believing that savings have been achieved is a fallacy. Don't stop there! Having thoroughly studied the market for energy-saving equipment, one comes to the understanding that real savings begin with installation thermomiser. After all, this device should be used in every heating and hot water supply system! Thermomizer is automatic temperature controller, How hot water, and the coolant. By equipping your system with a thermomiser, you get the ability to control the climate in any room and enormous savings in hot water or coolant consumption, and as a result, money.

How does a thermomiser work?

The thermomiser consists of only two components: a regulator and electronic device management. The first component, the regulator, is responsible for automatically regulating the temperature of the supply water for the heating or hot water supply system. The second component of the thermomiser is an electronic device that receives data from temperature sensors located inside and outside the room, as well as at the inlet and outlet of the coolant. The received data is processed in accordance with the program algorithm, calculations are made, according to which commands are sent directly to the controller.

What can thermomisers do?

By selecting various programs, we have the opportunity to maintain the set water and coolant temperatures, the heating system schedule, adjust the temperatures of the return circuit, the coolant in the supply pipeline based on deviation from the set internal room temperature, adjustment when using a timer, separate modes for holidays, weekends and nights, and a number of other options. Thermomizers are equipped with rich functionality and saving opportunities; we only need to select the desired model, set the necessary data and configure the mode.

An important detail in saving is the equipment of the device street sensor, this is especially true for spring, during sudden changes in temperature between night and day. By monitoring the entire dynamics of changes, we always have the indoor temperature we need without wasting resources and money.

Which thermomiser to choose?

You should choose a thermomiser based on the existing water supply and heating system. Any thermomiser model will effectively save coolant and create the necessary microclimate in the room. Depending on the type of regulator, some thermomisers can be used in systems of public and administrative buildings, others will be more relevant in open system hot water supply and heating, the third type of thermomisers is better applicable in closed systems with pump mixing, or as an additional option in ventilation systems and air conditioning systems. The most influential factor on the savings of a thermomiser is the type of regulator.

Our factory manufactures and supplies all the lineup the following temperature controllers:
thermomiser R-2.T, thermomiser R-7.T, thermomiser R-8.T, Teplur control device and other components of ultra-efficient energy saving equipment. You can seek advice on the selection, purchase, delivery, installation and configuration of thermomisers using the specified contacts on the product page.

How long do thermomisers last and how are they used?

In terms of service life, thermomisers are almost eternal, but the quality of the coolant has a direct bearing on the lifespan of the device. Given the realities, the thermomiser will work freely for 15-20 years. Our factory produces regulators from high-quality metals such as stainless steel, brass and cast iron, which has a positive effect on the durability and smooth operation of the devices. This gives significant advantages over imported devices - competitors made of carbon steel, produced by Danfoss and others. The quality of the primary Russian coolant is significantly inferior to the European one, for which imported thermomisers are designed, their operation in domestic systems will be accompanied by many problems.

Thermomizers are not at all whimsical in maintenance. Basically, no Maintenance and is not required. It is enough to initially configure the regulator once. It is recommended to delegate installation to professionals.

Benefits when installing a thermomiser

Often, when the coolant passes through the circuit of the heating system, it does not cool down and has a high enough temperature to use it again. This is exactly what is done using a thermomiser. By recycling the coolant, we achieve significant savings. Administrative, residential and public buildings can be connected according to this scheme.

For times when we do not use the room, for example, on weekends or holidays, we can set the minimum coolant temperature on the thermomiser, which will entail a significant reduction in coolant consumption.

Thermomizers also allow you to save money thermal energy in production and retail areas. For this energy you have to pay a lot of money on the meter. Just imagine what an overpayment you get for weekends, holidays, night time and other cases when the premises are not in use. For all these cases, you can configure certain modes in the thermomizer regulator and not pay extra money for excess coolant consumption.

The advantages of thermomisers are expressed not only in money; we should not forget about comfort. After all, the ability to regulate and maintain the temperature at the required level is relevant for many rooms of various buildings and areas.

Temperature is an indicator of the thermodynamic state of an object and is used as an output coordinate when automating thermal processes. The characteristics of objects in temperature control systems depend on physical parameters process and apparatus design. That's why general recommendations It is impossible to formulate temperatures based on the choice of ACP and a careful analysis of the characteristics of each specific process is required.

Temperature regulation in engineering systems ah is performed much more often than the regulation of any other parameters. Range adjustable temperatures small. The lower limit of this range is limited by the minimum outside air temperature (-40 °C), the upper limit by the maximum coolant temperature (+150 °C).

TO general features Temperature ASR can be attributed to the significant inertia of thermal processes and temperature meters (sensors). Therefore, one of the main tasks when creating a temperature control system is to reduce the inertia of sensors.

Let us consider, as an example, the characteristics of the most common manometric thermometer in a protective case in engineering systems (Fig. 5.1). The block diagram of such a thermometer can be represented as a series connection of four thermal containers (Fig. 5.2): protective cover /, air gap 2 , thermometer walls 3 and working fluid 4. If we neglect the thermal resistance of each layer, then the thermal balance equation for each element of this device can be written as

G,Cpit, = a p? Sjі ( tj _і - tj) - a i2 S i2 (tj -Сн), (5.1)

Where Gj- the mass of the cover, air gap, wall and liquid, respectively; C pj- specific heat capacity; tj- temperature; a,i, a/2 - heat transfer coefficients; S n , S i2 - heat transfer surfaces.

Rice. 5.1. Schematic diagram manometric thermometer:

• 1 - protective cover; 2 - air gap; 3 - thermometer wall;
• 4 - working fluid

Rice. 5.2.

As can be seen from equation (5.1), the main directions for reducing the inertia of temperature sensors are;

• increased heat transfer coefficients from the medium to the cover as a result the right choice sensor installation location; in this case, the speed of movement of the medium should be maximum; all other things being equal, it is more preferable to install thermometers in the liquid phase (compared to the gaseous phase), in condensing steam (compared to condensate), etc.;
• reducing the thermal resistance and thermal capacity of the protective cover as a result of the choice of its material and thickness;
• reducing the time constant of the air gap due to the use of fillers (liquid, metal shavings); for thermocouples, the working junction is soldered to the body of the protective cover;
• selection of the type of primary transducer: for example, when choosing, it is necessary to take into account that the low-inertia thermocouple has the least inertia, and the manometric thermometer has the greatest inertia.

Each temperature control system in engineering systems is created for a very specific purpose (regulating the temperature of indoor air, heating or cooling fluid) and, therefore, is designed to operate in a very small range. In this regard, the conditions for using one or another ACP determine the device and design of both the sensor and the temperature controller. For example, when automating engineering systems, direct-acting temperature controllers with pressure measuring devices are widely used. So, to regulate the air temperature in administrative and public buildings When using ejection and fan coils of a three-pipe heating and cooling circuit, a direct-acting regulator of the RTK direct type is used (Fig. 5.3), which consists of a thermal system and a control valve. The thermal system, which proportionally moves the control valve rod when the temperature of the recirculation air at the inlet to the closer changes, includes a sensing element, a setpoint and actuating mechanism. These three nodes are connected by a capillary tube and represent a single sealed volume filled with a heat-sensitive (working) fluid. A three-way control valve controls the supply of hot or cold water to the ejection heat exchanger

Rice. 5.3.

a - regulator; b - control valve; c - thermal system;

• 1 - bellows; 2 - set point; 3 - tuning knob; 4 - frame;
• 5, 6 - regulators of hot and cold water respectively; 7 - rod; 8 - actuating mechanism; 9 - sensing element

closer and consists of a housing and regulatory bodies. As the air temperature rises, the working fluid of the thermal system increases its volume and the valve bellows moves the rod and the regulator, closing the passage of hot water through the valve. When the temperature increases by 0.5-1 °C, the regulating bodies remain motionless (hot and cold water passages are closed), and with more high temperature Only the cold water passage opens (the hot water passage remains closed). The set temperature is ensured by rotating the adjustment knob connected to the bellows, which changes the internal volume of the thermal system. The regulator can be adjusted to temperatures ranging from 15 to 30 °C.

When regulating the temperature in water and steam heaters and coolers, RT type regulators are used, which differ slightly from RTK type regulators. Their main feature is the combined design of a thermal cylinder with a set pointer, as well as the use of a double-seat valve as a regulating body. Such pressure regulators are available in several 40-degree ranges ranging from 20 to 180 °C with a nominal diameter from 15 to 80 mm. Due to the presence of a large static error (10 °C) in these controllers, they are not recommended for high-precision temperature control.

Manometric thermal systems are also used in pneumatic P-regulators, which are widely used for temperature control in engineering air conditioning and ventilation systems (Fig. 5.4). Here, when the temperature changes, the pressure in the thermal system changes, which, through the bellows, acts on the levers that transmit force to the pneumatic relay rod and membrane. When the current temperature is equal to the set one, the entire system is in equilibrium, both pneumatic relay valves, supply and bleed, are closed. As the pressure on the rod increases, the supply valve begins to open. Pressure is supplied to it from the compressed air supply network, as a result of which a control pressure is formed in the pneumatic relay, increasing from 0.2 to 1 kgf/cm2 in proportion to the increase in the temperature of the controlled environment. This pressure activates the actuator.

For automatic control of indoor air temperature, they have begun to be widely used thermostatic valves American company Honeywell and radiator thermostats (thermostats) RTD produced by the Moscow branch

Rice. 5.4.

with manometric thermosystem:

• 1 - pneumatic relay rod; 2 - unevenness node; 3, 9 - levers;
• 4, 7 - screws; 5 - scale; 6 - screw; 8 - spring; 10 - bellows;
• 11 - membrane; 12 - pneumatic relay; 13 - thermal cylinder; 14 - nourishing

valve; 15 - bleed valve

Danish company Danfoss, the required temperature is set by turning the adjusted handle (head) with a pointer from 6 to 26 °C. Lowering the temperature by 1 °C (for example, from 23 to 22 °C) allows you to save 5-7% of the heat consumed for heating. Thermostats RTD make it possible to avoid overheating of premises during transitional and other periods of the year and to ensure the minimum required level of heating in premises with periodic occupancy. In addition, radiator thermostats RTD provide hydraulic stability for a two-pipe heating system and the possibility of its adjustment and coordination in case of errors during installation and design without using throttle washers and other design solutions.

The thermostat consists of a control valve (body) and a thermostatic element with a bellows (head). The connection between the body and the head is made using a threaded union nut. For ease of installation on the pipeline and connection of the thermostat to the heating device, it is equipped with a union nut with a threaded nipple. The room temperature is maintained by changing the water flow through the heating device (radiator or convector). The change in water flow occurs due to the movement of the valve stem by a bellows filled with a special mixture of gases that change their volume even with a slight change in the temperature of the air surrounding the bellows. The elongation of the bellows as the temperature rises is counteracted by an adjustment spring, the force of which is regulated by turning the handle with an indicator of the desired temperature value.

To better suit any heating system, two types of regulator housings are available: RTD-G with low resistance for single-pipe systems and RTD-N with increased resistance for two-pipe systems. Housings are manufactured for straight and angle valves.

Thermostatic elements of the regulators are manufactured in five versions: with a built-in sensor; with remote sensor (capillary tube length 2 m); with protection against inept use and theft; with the setting range limited to 21 °C. In any design, the thermostatic element ensures that the set temperature range is limited or fixed at the required air temperature in the room.

Regulator service life RTD 20-25 years, although at the Rossiya Hotel (Moscow) the service life of 2000 regulators is registered for more than 30 years.

Regulating device (weather compensator) ECL(Fig. 5.5) ensures maintenance of the coolant temperature in the supply and return pipelines of the heating system depending on the outside air temperature according to the corresponding specific repair and specific object heating schedule. The device operates on an electrically driven control valve (and, if necessary, on the circulation pump) and allows the following operations:

• maintaining settlement heating schedule;
• night decline temperature chart according to weekly (2-hour intervals) or 24-hour (15-minute intervals) programmable clocks (in the case of electronic clocks, 1-minute intervals);
• flooding the room for 1 hour after an overnight drop in temperature;
• connection via relay outputs of a control valve and a pump (or 2 control valves and 2 pumps);

Rice. 5.5. EU weather compensator/. with setting,

available to the consumer:

1 - programmable clock with the ability to set periods of operation at a comfortable or reduced temperature on a daily or weekly cycle: 2 - parallel movement of the temperature graph in the heating system depending on the outside air temperature (heating graph): 3 - operating mode switch; 4 - space for operating instructions: 5 - switch-on signaling, current operating mode,

emergency modes;

O - heating is turned off, the temperature is maintained to prevent freezing of the coolant in the heating system;) - work with low temperature in the heating system; © - automatic switching from a comfortable temperature mode to a reduced temperature mode and back in accordance with the setting on the programmable clock;

O - work without lowering the temperature on a daily or weekly cycle; - manual control: the regulator is turned off, the circulation pump is constantly on, the valve is controlled manually

• automatic transition from summer mode in winter and back at a given outside temperature;
• stopping night temperature reduction when outside temperatures drop below a set value;
• protection of the system from freezing;
• correction of the heating schedule based on room air temperature;
• transition to manual control of the valve drive;
• maximum and minimum restrictions on supply water temperature and the possibility of fixed or proportional

on-line limitation of return water temperature depending on the outside air temperature;

• self-testing and digital indication of temperature values ​​of all sensors and states of valves and pumps;
• setting the dead band, proportional band and accumulation time;
• the ability to work using temperature values ​​accumulated over a given period or current values;
• setting the thermal stability coefficient of the building and setting the influence of the return water temperature deviation on the supply water temperature;
• protection against scale formation when working with gas boiler. Automation schemes for engineering systems use

also bimetallic and dilatometric thermostats, in particular electric two-position and pneumatic proportional.

The electrical bimetallic sensor is intended mainly for two-position temperature control in rooms. The sensitive element of this device is a bimetallic spiral, one end of which is fixedly fixed, and the other is free and meets moving contacts that close or open with a fixed contact depending on the current and set temperature values. The set temperature is set by turning the setting scale. Depending on the setting range, thermostats are available in 16 modifications with a total setting range from -30 to + 35 °C, and each regulator has a range of 10, 20 and 30 °C. Operation error ±1 °С at the middle mark and up to ±2.5 °С at the extreme marks of the scale.

The pneumatic bimetallic regulator, as a converter-amplifier, has a nozzle-flap, which is acted upon by the force of the bimetallic measuring element. These regulators are available in 8 modifications, direct and reverse acting, with a total adjustment range from +5 to +30 °C. The setting range for each modification is 10 °C.

Dilatometric regulators are designed using the difference in the linear expansion coefficients of an Invar (iron-nickel alloy) rod and a brass or steel tube. These thermostats, in terms of the operating principle of the control devices, do not differ from similar regulators using a manometric measuring system.

Temperature controls in individual rooms

Thanks to the Danfoss radiator thermostat, only the required amount of energy is used, and the room temperature is constantly maintained at the required level. The thermostat measures the room temperature and automatically adjusts the heat supply.

It allows you to avoid overheating of premises during transitional and other periods of the year and to ensure the minimum required level of heating in rooms with periodic occupancy (system freezing protection).

Short name for radiator thermostatRTD(Danfoss Radiator Thermostat). What is a radiator thermostat?

1 - combination of room temperature sensor and water valve,

2 - independent pressure regulator (works without an additional energy source)

3 - a device that constantly maintains a set temperature.



Operating principle of a radiator thermostat:

The principle of operation is the balance between the force of the medium (in in this case: gas) and the force of the pressure spring, the magnitude of which depends on the setting of the head (to the required temperature). Thus, the amount of flow through the valve depends on the setting of the head and the ambient temperature sensed by the sensor.

If the temperature rises, the gas expands and thus closes the valve slightly. If the temperature drops, the gas is compressed accordingly, which leads to the opening of the valve and access of the coolant to the heating device.

The use of gas gives Danfoss a big advantage over other manufacturers: the low time constant, which is expressed in better use free heat through a quick response to changes in room temperature (reaction time).

Today, only Danfoss radiator thermostats use the principle of gas expansion and compression. The reason is that using gas requires very modern technology and, accordingly, high quality requirements. However, Danfoss is willing to incur additional costs in order to achieve high-quality and competitive products.

The choice of radiator thermostat depends on the following conditions:

sensor type Y valve location

valve type Y radiator size (heat requirement), temperature drop by heating element, type of heating system (1- or 2-pipe system)

Why is it necessary to use a radiator thermostat?

1 - because it makes it possible to save thermal energy (15-20%), allows the use of free, “free” heat (solar radiation, additional heat from people and devices), its payback period< 2 лет.

2 - provides high level indoor comfort.

3 - ensures hydraulic balance - it is very important to create hydraulic balance in heating system, which means supplying available thermal energy to each consumer according to his needs.

RTD thermostatic heads (20% heat saving)




Heads for radiator thermostats are manufactured in the following versions:

RTD 3100 / 3102 - standard sensor, built-in or remote, temperature range 6-26° C, limiting and fixing temperature settings.

RTD 3120 - tamper-proof sensor, built-in, temperature range 6 - 26° C, frost protection.

RTD 3150 / 3152 - sensor with maximum temperature limitation, built-in or remote, temperature range 6 - 21 ° C, frost protection, temperature setting fixation.

series RTD 3160 - element remote control, capillary tube length 2 / 5 / 8 m, Maximum temperature 28° C with limitation and fixation of temperature settings (for radiators and convectors inaccessible to the user).

The remote sensor must be used if the built-in sensor will be affected by a draft or if it is hidden behind curtains or decorative grilles.

The thermostatic head itself is easily secured to the valve using a union nut. The head can be protected against unauthorized removal using a screw (ordered separately as an additional accessory).


Valves RTD-N and RTD-G

When Danfoss began expanding into markets outside Western Europe, the company's specialists carried out numerous analyzes of water quality in different countries. As a result of this experience, it became clear that poor water quality is common in heating systems in some countries. In this regard, a new series of valves was developed for the Eastern European markets - the RTD series.

The materials used in the RTD remain particularly resistant to low water quality (compared to valves produced for Western European markets, we replaced all tin bronze parts with more resistant brass ones). This means that the service life of the valve is significantly increased, even in difficult conditions of Ukraine. We know from experience that the average valve life is up to 20 years.

Type control valvesRTD-N(diameters 10-25 mm) are intended for use in two-pipe pumping systems water heating and are equipped with a device for preliminary (installation) adjustment of their throughput.

In a 2-pipe heating system, adding water beyond the design volume leads to increased heat transfer and an imbalance in the system. The valve presetting function allows the installer to limit the valve capacity so that the hydraulic resistance in all radiator circuits is the same and thus regulate the flow rate.

Simple and precise bandwidth adjustment is easily done without additional tool. The number stamped on the setting scale must be aligned with the mark located opposite the valve outlet. The valve capacity will change according to the numbers on the setting scale. In position “N” the valve is fully open.

Protection against unauthorized changes to the setting is provided by a thermostatic element installed on the valve.

Control valves with increased throughput typeRTD-G(diameters 15-25 mm) are intended for use in pump single-pipe water heating systems. They can also be used in two-pipe gravity systems. Valves have fixed capacity values ​​depending on the valve diameter.

Example of radiator thermostat calculation:

Heat demand Q = 2,000 kkal/h

temperature difference D T = 20 ° C

existing pressure loss D P = 0.05 bar

We determine the amount of flow (water flow) through the device:

Water flow G = 2,000/20 = 100 l/h

We determine the valve capacity:


Valve capacity Kv = 0.1/C 0.05 = 0.45 m3/bar



The value Kv = 0.45 m3/h means that for the RTD-N 15 mm valve you can select the preset “7” or “N”.

When choosing a radiator thermostat, it is necessary to ensure adjustment in the range from 0.5 ° C to 2 ° C for given dimensions, which will ensure good conditions regulation. In our case, it is necessary to select the preset “7” or “N”. However, if there is a danger of contaminated water in the heating system, we do not recommend using a preset lower than “3”.

Using our technical description “Radiator thermostats RTD”, you can select the valve size directly from the diagrams through the pressure loss across the valve D P, or through the flow value through the valve G. The selection of the size of the RTD-G valves (for a 1-pipe system) is carried out identically.


New construction

In new buildings we recommend the use of a 2-pipe system with RTD-N valves, with pre-adjustment to maintain hydraulic balance in the system, DN 10-25 mm, straight and angled versions.



Reconstruction

The vast majority of older buildings use a 1-pipe system, for which we recommend RTD-G valves with increased capacity (fixed capacity values ​​depending on the diameter), DN 15-25 mm, straight and angled versions.

Especially for RTD-N valves with presetting, the use of a filter is very important to prevent interference with the normal functioning of the valve.


Balancing valves ASV series

Since radiator heating systems are dynamic systems (different pressure drops due to reduced heat load), radiator thermostats must be combined with pressure regulators (automatic balancing valves ASV-P for a 2-pipe system) and a shut-off valve MV-FN.

The ASV series of regulators includes two types of automatic and manual balancing valves:

automatic valve ASV-PV - differential pressure regulator with variable setting 5 - 25 kPa

valve ASV-P - regulator with fixed setting at 10 kPa

ASV-M - manual shut-off valve

ASV-I - shut-off and metering valve with adjustable capacity

ASV ensures optimal distribution of the coolant along the risers of the heating system and the normal functioning of the latter, regardless of pressure fluctuations in the system. They also allow you to close and empty the riser. The maximum operating pressure is 10 kPa, the maximum operating temperature is 120° C.

The styrofoam packaging in which the valve is transported can be used as a heat-insulating shell at a coolant temperature of up to 80° C. At a maximum operating coolant temperature of 120° C, a special heat-insulating shell is used, which is supplied upon additional order.



Automatic flow regulator ASV-Q

For hydraulic balancing of 1-pipe heating systems, automatic flow limiting valves ASV-Q are used - diameters 15, 20, 25 and 32 mm (setting range from 0.1-0.8 m3/hour to 0.5-2.5 m3 /hour). They are used to automatically limit the maximum value of water flow through the riser, regardless of fluctuations in pressure and coolant flow in the system and for optimal distribution of coolant along the risers of the heating system

These valves are especially useful for balancing heating systems for which hydraulic performance data is not available. ASV-Q always provides the coolant flow for which the valve is set. When the system characteristics change, the controller automatically adjusts.

Installing ASV-Q valves eliminates the need for traditionally complex commissioning work in new construction and reconstruction of heating systems, including expansion of systems without hydraulic calculation of pipelines.



Application (examples 1 - 2 pipe systems)

When reconstructing a single-pipe system without a bypass (flow-through system), it is necessary to install radiator thermostats on heat radiation sources (RTD-G and RTD heads) and install a bypass line (bypass), the cross-section of which should be one size smaller than the main pipe of the system (bypass in 1/2" for the main one in 3/4").

With the help of a bypass, the coolant flow through the heat radiation source is reduced to 35 - 30%, which also depends on the diameter of the main pipes in the system. By studying the heat transfer curve of a radiator of a single-pipe system, we are convinced that reducing the coolant flow from 100% to even 30% will lead to a decrease in the heat transfer of the radiator by only 10%.

This means that in the vast majority of cases, installing a bypass will have only a minor effect on heat transfer. In many cases, the dimensions of the heat emitter (radiator, convector) have already been selected with a margin, and therefore the heat emitters can continue to provide the required amount of heat. If the radiator is low-power, then to solve the problem you need to:

- Increase the coolant temperature

- Increase the performance of the circulation pump

- Increase heating surfaces of radiators

-Insulate the building envelope (walls)

RTD-G high flow valves are used in single pipe heating systems with circulation pumps and in two-pipe gravity (gravity) systems.

To maintain hydraulic balance in the heating system, it is necessary to install an automatic flow regulator ASV-Q on each riser, which will limit the flow through each riser. In this way, the heat will be distributed evenly across all risers, especially in the case of changing heat loads or if there is an insufficient heat supply. The ASV-M shut-off and metering valve allows you to shut off each individual riser and, if necessary, drain water from it, while simultaneously measuring the flow through the riser.

Heat emitters (radiators and convectors) can be equipped with radiator thermostats (RTD-G and RTD heads) without any restrictions. The selection of the RTD-G valve is carried out in accordance with the previous example (see also the example of the selection of RTD-G in the technical description). In this case, the risers must be equipped with flow limiters ASV-Q and ASV-M shut-off and metering valves.

In the case of a 2-pipe system, heat emitters can be equipped with radiator thermostats (RTD-N and RTD sensors) without any restrictions. The selection of the RTD-N valve is carried out in accordance with the examples given above for the RTD-N. In this case, each riser should be equipped with an ASV-P pressure regulator (and an ASV-M shut-off and metering valve), which will provide a constant D P on each riser, thereby compensating for changes in the thermal load and changes in D P. Moreover, reducing the risk noise in radiator thermostats, the differential pressure regulator will thereby ensure their durability


This solves the issue of adjusting the temperature in individual rooms.

In this article we will find out what thermostats for home heating can be. We will analyze the basic principles of operation of different devices of this type and tell you how to install them correctly. Let's start, however, with a few general concepts.

Why is this necessary?

But really, why do you need a thermostat for heating? Our grandparents managed well without him and did not suffer at all...

Saving

Remember what rent was like in your grandparents' time? At the end of the seventies, in two-room apartment on Far East, where the author grew up, it was approximately 15 rubles. In winter, along with heating and electricity.

For comparison: the salary of a junior researcher at a local institute was then approximately 120 rubles. average salary in the city, thanks to the northern and regional coefficient - more than two hundred. It never occurred to anyone to worry about the two or three rubles they overpaid for excess heat: it was easier to open the window.

However: even at the project level, all radiators were equipped with the great-grandfather of current thermostats - a three-way valve. It made it possible to reduce the coolant flow through the radiator by completely or partially directing the water flow to the jumper.

Now most of the state’s initiatives come down to two main theses:

1. Citizens don't need this.
2. And they must pay for this themselves.

There are no more subsidies for housing maintenance, housing and communal services are in decline, rents are rising, but we... adapt as best we can.

Thermostats for heating radiators in combination with heat meters are one of the ways to reduce the cost of heating your home. Heat is consumed exactly as much as is necessary to maintain a comfortable temperature at home. Not more.

Convenience

Yes, thermostats are not the only tool with which you can save heat. Heating radiators can also be adjusted manually - using a throttle or a regular valve.

But, as usual, there are nuances:

• The throttle regulates the passage of the line. When the temperature of the coolant fluctuates, the heat transfer of the heating device will also change.
• Heat demand varies depending on the outside temperature. Manually adjusting the flow of a throttle or valve several times a day is somewhat tedious.

An alternative to a throttle, a thermostat is a fully automatic and weather-sensitive heating regulator. If the room becomes hot due to the rising temperature of the water in the radiator, it will reduce the flow of water through it.

If it gets cold, it will open slightly. And all this will happen without your participation.

Principle of operation

There are an infinite number of specific implementations of heating controllers. It is based on only two basic principles adjustments.

Mechanical regulator

Let's see how the Danfoss RAW-K 5030 thermostatic head works.

• The mechanism is based on a container with liquid or gas with a high coefficient of thermal expansion. The container tends to press the valve, blocking the flow of water; it is opposed by a conventional spring.
• Rough adjustment is carried out using a simple screw mechanism. The closer the initial position of the temperature-sensitive element is to the valve, the less travel it needs to shut off the flow of water.
• In addition, many thermostats for heating radiators include an additional adjustment mechanism - a simple throttle. It helps to calibrate the thermostat so that the scale of conventional values ​​​​on it corresponds to real temperatures in the range from 7 to 28 degrees.

However: precise adjustment can be made with an ordinary throttle mounted on a second supply to the heating device, free from the thermostat.

The same principle is used, by the way, by an automatic draft regulator for solid fuel boilers. The problem of discrepancy between the damper stroke and changing the size of the heat-sensitive container is solved extremely simply - by using a lever with arms of different lengths.

Electrical regulator

All electric heating thermostats use the ability of some materials to change their characteristics when the temperature changes.

Of course, in this case we are talking about electrical characteristics:

• The thermistor changes its resistance as the temperature changes. Accordingly, at a constant voltage, more or less current will flow through it. This is how, for example, the heater fan speed controller often works. With low power consumption, all current can flow directly through the thermistor.

A more complex circuit, however, will make it possible to control larger currents. So it works room regulator heating VRT 40 from Vaillant: with a current through the thermistor of a fraction of an ampere, it can control electric boiler power of tens of kilowatts.

• The thermocouple is an even more interesting device. If two plates made of different metals are soldered together - for example, nichrome and an aluminum-nickel alloy - a potential difference will arise at the junction. Moreover, it will change dynamically with fluctuations in the temperature of the adhesion point.

The resulting current will be in the millivolt range and is not sufficient by itself to move any valve; however, that's what transistors are for. The control signal can be arbitrarily small and still control large currents.

A cascade of transistors will theoretically allow an ordinary thermocouple to control the heat supply not only to a radiator, but even to an entire apartment building.

At general principle The operation of electrical thermostats can be analog or digital. The first allow only the simplest temperature setting and are most often equipped with a simple indicator combined with a control - a wheel with a scale. The latter can not only set the current temperature, but also be programmed for a day or a week.

In addition, digital indicators are divided into two more categories:

• Devices with closed logic allow only setting basic parameters within the factory firmware. They are relatively easy to set up, but have limited capabilities by the manufacturer. A typical example is the Calormatic 430 automatic heating controller from Vaillant.

• Open logic devices can be completely reprogrammed. Instead of the so-called one-time chips - non-erasable microcircuits with firmware - they are equipped with regular flash memory with an open interface.

These devices are rarely used in heating systems of private houses: the difficulty of setting up and the high price scare off buyers. But the capabilities of a heating thermostat with open logic are impressive.

Here is a list of functions of the Ukrainian heating regulator Takeoff RO-2:

• Temperature control taking into account the thermal inertia of the building.
• Calculation of temperature graph compensating sharp fluctuations outside temperature.
• Protection of the heating network from overloads by rationing hot water consumption.
• Construction of a temperature chart for administrative buildings, taking into account their operating modes.
• Calculation of coolant consumption in accordance with the current agreement with the heat supplier.

It's easier to say what this thermostat can't do. In addition, if additional functions are required, it can be reflashed.

Installation rules

Thermostatic heads

If heating radiators with a thermostat are supplied ready for connection, then a thermostat purchased separately must also be installed.

How to do it yourself correctly?

• The installation method itself is no different from assembling other threaded connections. Do not forget about the fragility of the brass body: when assembling threaded connections, avoid great force. The best winding for threads, which is easy to find in any store, is plumbing linen; to make it more durable, soak a strand of flax with any paint.
• The thermostat for heating radiators is always located on the supply line. On the return thread there will be great idea install a valve that allows you to completely shut off the heating device. If the thermostatic head does not have a throttle built into it for manual calibration, the valve can be replaced with a separate throttle.

Attention: the presence of a jumper when installing ANY throttle or thermostat is mandatory. Without it, you will regulate the flow of the riser or the entire heating circuit of a private house.

• In the case of a two-pipe heating system, the use of chokes is mandatory. They are needed to balance the circuit: the batteries closest to the boiler or elevator will have to be pressed, reducing the coolant flow through them. Otherwise, distant radiators simply will not heat up - even to the point of defrosting in extreme cold.

Balancing is performed with the thermostatic heads fully open (maximum temperature value on the dial). Only after all heating devices begin to heat up to approximately the same temperature can the thermostats be adjusted and calibrated.

• If you are installing a heating system in a one-story private house, best choice The Leningradka will become a single-pipe circuit around the perimeter of the house, parallel to which, without disconnecting it, heating devices are installed.

The connection diagram is bottom or diagonal. A choke is installed on one of the connections (balancing is not necessary here, but is desirable). The second one is the thermostat.

• The head is usually placed horizontally. What is the instruction related to? The fact is that when installed vertically, the heat-sensitive element will often fall into the flow of hot air rising from the radiator. It is clear that its temperature will have little to do with the AVERAGE temperature in the room.

Electronic regulators

Installation rules depend on where the temperature sensor of the regulator is located.

If it is built into the control panel, it must be mounted in accordance with quite understandable restrictions:

• The height above the floor is at least 80 centimeters. Close to the floor the temperature is noticeably lower. Especially when the window or door to the hallway is open.
• Outside of rising air currents from any heating devices and generally heating structures. Heat from the back of the refrigerator will affect sensor calibration just as much as a radiator.
• Direct sunlight will also affect the operation of the device. Place the sensor panel in the shade.
• Finally, it would be unwise to locate the electronic control panel where the wall is often touched by people passing nearby.

If the thermostat uses a remote sensor, all points except the last one will relate specifically to the location of the sensor. The panel is mounted where it is convenient for you.

Conclusion

In the video at the end of the article you can become more familiar with some types of thermostats and the rules for their installation. U different manufacturers Installation requirements may vary quite a bit, so be sure to read the instructions.