How to adjust the balancing valve in a heating system. Design and installation of a balancing valve for a heating system. What is a balancing valve?
Conventional ball valves cannot regulate the flow of water in pipes or radiators. But for proper distribution of coolant among the batteries, such adjustment is necessary. Manual balancing valve(otherwise known as a valve) is precisely used to configure the water heating system. In this publication we will tell you where the balance valve is installed and how to use it correctly when balancing the heating network of a private home.
Why are balancing valves needed?
Let us immediately make a reservation that not every system requires balancing as such. For example, 2-3 short dead-end branches with 2 batteries on each can immediately switch to normal operating mode, provided that the pipe diameters are selected correctly and the distances between the devices are small. Now let's look at 2 situations:
- 2-4 heating branches of unequal length with a number of radiators from 4 to 10 are connected to the boiler.
- The same situation, but with batteries equipped with thermostatic valves (described in).
Since the bulk of water always flows along the path of least hydraulic resistance, in situation No. 1 the first heating devices located close to the boiler will receive more heat. If the flow of coolant to these radiators is not limited, then the last batteries in the chain will heat up much less, the temperature difference between them can be 10 ° C or more.
To direct the required amount of coolant to distant batteries, radiator balancing valves, shown in the photo, are installed on the connections to nearby devices. They restrict the flow of water, partially blocking the flow area of the pipes and increasing the hydraulic resistance of the area.
In the same way, the coolant supply is regulated in systems with five or more dead-end branches. Manual balancing valves intended for pipelines are installed on the tie-ins close to the heat generator. Partially blocking the passage of water, they direct the main flow further along the highway.
Situation #2 is more complicated. Installing radiator thermostats with heads allows you to change the coolant flow automatically as needed. But imagine that in the room closest to the boiler the window opened, the air temperature dropped, and the thermostat opened completely. Then the last room will also become colder, because it will not have enough heat taken away by the first battery.
The purpose of the valves is to limit the coolant flow to the risers (or horizontal branches) On long branches with a large number heating devices, equipped with thermal heads, balancing valves are combined with automatic differential pressure regulators, as is done above in the diagram.
Regulators connected by capillary tubes to balance valves respond to a decrease/increase in water flow and maintain the return pressure at the same level. Then all consumers have enough coolant, despite the activation of the thermal valves. The benefits of such control taps are described in detail in the video:
Where should the valve be installed?
In most private homes, only manual radiator valves are used. They are quite enough to set up normal work water heating in cottages up to 500 m². Installation of main-type balance valves is carried out in the following cases:
- in buildings with an extensive heating network consisting of many risers;
- V apartment buildings, heated by their own boiler room;
- at .
Once we have figured out the purpose of balancing valves, we will indicate specific locations for their installation. Radiator taps should be installed at the outlet of the batteries, and main taps should be installed on the return pipe with cooled coolant. If the element is used in conjunction with automatic regulator pressure, then it can stand on both the supply and return pipelines, depending on the designed circuit.
An example of a scheme with group balancing of risers Reference. In aluminum and steel radiators with bottom connection balancing valve built into special fittings, intended for connecting connections to such devices.
Let us highlight the moments when it is not necessary to install control valves:
- in dead-end systems of short length with hydraulically equal “shoulders”;
- if all batteries are equipped with preset thermostatic valves;
- on the last (dead-end) radiator;
- in collector-type heating systems.
Special fittings for bottom connection are equipped with built-in balancing valves Temperature regulators with presetting, located at the water supply to the battery, simultaneously play the role of a balance valve, so it is enough to install a shut-off ball valve at the outlet of the heating device. The same fittings are mounted on the connections of the last radiator in the chain, since there is no point in adjusting it; it must be completely open.
Design and operating principle
The radiator tap, designed for manual balancing of heating, consists of the following parts:
- Brass body with threaded pipe connections. Inside, a saddle is made by casting - vertical round channel, slightly expanding at the top.
- A shut-off and regulating spindle with a working part in the form of a cone, which enters the saddle when twisted and limits the flow of water.
- O-rings made of EPDM rubber.
- Protective plastic or metal cap.
The figure shows a valve from Caleffi (website – https://www.caleffi.com) Note. All well-known manufacturers - Danfoss, Herz, Caleffi and others - offer 2 types of valves - straight and angular. The principle of operation is the same, only the shape changes.
The device of the balancing valve is shown in more detail in the diagram above. It shows that rotation of the spindle leads to an increase or decrease in the flow area, and this is how the adjustment is made. The number of revolutions from the closed to the maximum open position is from 3 to 5, depending on the valve manufacturer. To turn the rod, you need to use a regular or special key in the form of a hexagon.
Main taps differ from radiator taps in size, inclined position of the spindle and fittings designed for:
- coolant drain;
- connecting measuring instruments;
- connecting the capillary tube from the pressure regulator.
Main valve device for balancing heating branches For reference. Radiator valve models, for example, from the Oventrop brand, are also equipped with a drain pipe.
The range of balance cranes is constantly expanding due to the emergence of new high-tech products. An example is an Italian-made Caleffi vertical valve equipped with a flow meter.
The Caleffi valve with flow meter can be mounted in 2 positions - horizontal and vertical How to balance a radiator network
Typically, heating system installers set the coolant flow rate on the radiators in a simple way: divide the number of revolutions of the balancing valve by the number of heating devices and in this way calculate the adjustment step. Moving from the last radiator to the first, close the taps with the resulting difference in speed.
Example. On one “arm” of the dead-end system we have 5 radiators with Oventrop manual valves with 4.5 spindle turns. Divide 4.5 by 5, we get an adjustment step of about 0.9 turns. This means that we open the penultimate heating device by 3.6 turns, the third by 2.7, the second by 1.8, and the first by 0.9 turns.
The method is quite approximate and does not take into account the different power of batteries, and therefore can be used as a preliminary setting with adjustments during operation.
A contact thermometer that measures the surface temperature of pipes and radiators will help you balance your heating more accurately. Our experienced one offers another technique based on measuring the actual surface temperature of the heaters. The step-by-step balancing instructions look like this:
- Open all balancing valves as much as possible and put the system into operating mode with a supply temperature of 80 °C.
- Use a contact thermometer to measure the temperature of all heating devices.
- Eliminate the resulting difference by tightening the taps of the first and middle radiators; do not touch the final ones. Open the near battery by 1-1.5 turns of the valve, the middle ones by 2-2.5.
- Allow the system to adapt to the new settings for 20 minutes and repeat the measurements. Your task is to achieve a minimum temperature difference between the battery farthest and closest to the boiler.
Note. The weather and outside temperature do not matter, only the difference in the heating of the radiators is important. By the way, in normal operating mode at 50-70 °C at the supply temperature delta will become even lower. How the system is hydraulically balanced using balancing valves, watch the video from an expert:
Final Conclusion
If you install heating yourself, you will probably encounter balancing problems. When all radiators, except the last one, have balancing valves, the procedure will not cause much trouble. It's better to take valves, key adjustable or a screwdriver, not a plastic handle, so that children cannot get to them. It is possible that in winter the position of the spindles will have to be adjusted, because the rooms are different. The only caveat: do not make sudden movements and open the taps in cold rooms slowly, ¼ turn at a time.
Good day to everyone who reads this post! In it I will tell you about balancing valves for heating systems. Let's start by figuring out why a balancing valve is needed in a heating system.
Why is a balancing valve needed?
In modern large systems ah heating is often observed uneven heating different rooms. This is due to different consumption coolant through the branches of the heating system. Coolant (as electricity) tries to flow along the path of least resistance, therefore, at a great distance from the heat source (thermal unit or boiler), the flow rate should be less than near it. In order to equalize the coolant flow through different branches, balancing valves are used.
As can be seen from the top figure, the flow rate in heating circuits of different lengths will be different and the temperature in the rooms will also differ dramatically. Now let's talk about the types of balancing valves.
Types of balancing valves.
Balancing valves come in two main types:
Danfoss has done very interesting video about the operation of manual balancing valves. I advise you to watch this video from beginning to end. It shows unexpected patterns of operation of this type of valve:
From the figure it is clear that internal organization An automatic balancing valve resembles a piston pressure reducer, but the functions of these devices are completely different. I bring to your attention two videos on this topic:
To simplify the setup of heating systems, special measuring instruments, which simplify and speed up system balancing. Look at the picture below:
Installation of balancing valves.
The installation of a balancing valve is carried out in the same way as the installation of ball valves. The position of the valve in space does not affect its operation, but you need to pay attention to the arrow, which indicates the recommended direction of flow. If it is mixed up, the valve will create greater resistance to the flow of coolant. Valves can be installed on both supply and return pipelines.
Operating temperature and pressure may vary depending on the specific model, so it is best to select the equipment you need using manufacturer catalogs. You can find them on the official websites of manufacturers.
Summary.
Installation of balancing valves is necessary in large heating systems. They allow optimal distribution of coolant throughout all circuits. For the operation of such equipment, it is important correct installation and subsequent setup. It is necessary to consider the installation of valves at the design stage of the system. That's all, I'm waiting for your questions in the comments!
Many people believe that a heating system is simply a set of pipes and radiators, which are complemented by a heating boiler and circulation pump. But it is not so. The heating system also contains whole line auxiliary components, without which the work would not be entirely of high quality. One of these elements is a balancing valve for heating systems.
Application area
Valve (tap) required for hydraulic balancing of hydraulic circuits. It can control the permissible flow rate of coolants. As a result, work efficiency heating system will increase significantly.
The balancing valve is needed to heating distribution was the same throughout the entire water supply. This means that hot liquid comes to the battery in the amount that is needed and is evenly distributed throughout the room. It should be noted that it can also operate under strong pressure drops and high speed movements of the working environment.
Design
The design of the balancing valve is based on the design of a ball valve, only with some additions. Additions include an indicator for the shutter, a measuring diaphragm, a pipe (the valve itself is installed on it) and a special position lock. The body is made of steel, silumin or brass. Used as a sealant membrane system. Such balancing valves will cost significantly more, but they do not require any maintenance.
The seat and valve of the balancing valve distributes the fluid flow. The valve stem can be: rising, falling, oblique or straight. When purchasing a balancing valve, these stem features must be taken into account.
The rod, with an oblique shape, has less hydraulic resistance. Such balancing valves have high control precision and good flow characteristics.
Main characteristics
In addition to regulating heating flow, the balancing valve has some other devices and settings. For example, it can adjust stepwise or smooth flow setting, can block presets, regulate the operation of the bypass valve and regulate the operation of a special temperature fuse.
Balancing valves (regardless of their design) have the following characteristics:
- The operating temperature can be from -20 to 120 degrees.
- It has the minimum length required for installation.
- All information is read directly. No additional devices are needed.
- No excess weight. This is possible thanks to its compact size.
- Since the valve is made of durable material, it will not be deformed.
Balancing valve in the heating system
Depending on the number of heating circuits, it is installed required quantity balancing valves. The type of heating system will determine the order in which valves are used for balancing.
Balancing valve in a private house
Some users believe that balancing should only be done in large rooms. But in a private house the heating system can have quite complex circuit , which includes several circuits, in each of which it is necessary to maintain a certain operating mode. To achieve this goal, a balancing valve is installed in each supply pipe.
Balancing valve in a multi-storey building or building
In this case, manual or automatic balancing valves are used. They are installed in order to maintain constant coolant flow.
It should be noted that during the construction of modern multi-storey buildings, the balancing valve is always used. The larger the heated room, the more balancing valves are installed. A balancing valve in any heating system allows you to save up to one to forty percent of all heat.
Installation
Installation occurs in accordance with installation rules pipeline systems except for minor subtleties.
It should be noted that the use of such valves allows you to save from twenty-five to forty percent of heat.
Where else can such a valve be used?
It can be used in systems with a solid fuel boiler. To do this, the valve must be installed in a small circulation circuit. Myself the circuit must be closed to the buffer capacitance. The point of such a connection is to maintain the water temperature in the circuit at least sixty degrees, and not set mixing unit. With this connection, the fuel consumption in the boiler circuit should be higher than in the heating circuit. For this purpose, a valve is needed, which is placed on the supply side of the system.
So, a balancing valve is a device necessary for heating systems. A balancing valve is needed in every heating system. Depending on the area of the room, the required number of valves is installed in the system for the correct operation of the entire system. Their use in heating systems will save from twenty-five to forty percent of heat, provided that the cost of the valve itself is no more than one percent of the total cost of the entire system.
Own living space provides daily responsibility. The level of comfort in the home is an indicator that makes it clear how successfully the responsibilities assumed are being fulfilled. To maintain comfortable living conditions, you need to pay attention every day a large number everyday aspects. One of them is the room temperature. How are balancing valves related to its condition? It turns out - in the most direct way.
The heating system is primarily responsible for the correct temperature conditions. Its varieties and types may differ in their complexity and structural components, but the result of the work should always be the same - the most comfortable room temperature for all residents at optimal costs. After all, problems with heating can lead to changes in the microclimate in an apartment or house, as well as to an increase in utility bills.
The operating principle of the heating system implies that the coolant moves from one unit to another. Radiators are filling up hot water and due to this, the main heating occurs, which should be sufficient for the entire living area. However, this does not always happen, because a perfectly functioning heating system can only exist on paper. One way or another, during operation the level of heat transfer decreases - the temperature and pressure level in the pipeline changes. This, in turn, affects the distribution of media throughout the system. Bottom line: one room can be a real tropics, and the second - an icy desert.
The problem is outlined: hot water is unevenly distributed through the pipes - comfortable temperature indoors is much more difficult to achieve. Now we need to find a solution. And it lies in the already mentioned phrase “balancing valves”.
What is a balancing valve?
Balancing valve (balancing valve, balancing valve) - view pipeline fittings and an important auxiliary element of the heating system. Its main function is the effective distribution of heat transfer.
Any heating system needs correct setting: the calculated heat transfer rates must coincide with the real ones. One of the most modern and convenient means for this is balancing valves. They are simple mechanical devices that work smoothly. Outwardly somewhat similar to the ones we are used to manual taps, but provide smoother and more flexible adjustment. The valve plays an important role in balancing the heating system and optimizing coolant flow.
We understand the purpose, but how do balancing valves work?
The principle of their operation is quite simple. By adjusting the valve, the size of the flow area changes. Following it is the pressure level in the area where it is installed. Accordingly, with an increase or decrease in cross-sectional size, the pressure level and flow rate change hot water, which goes to the radiators. This balancing of the heating system allows you to achieve maximum high efficiency her work. By adjusting the pressure level and media flow using a balancing valve, residents will be able to obtain the required amount of heat in each room. In addition, the design usually also has special inputs (fittings), thanks to which you can connect measuring devices and calculate the flow rate of the medium moving through the heating system.
It is probably difficult to understand the design of a balancing valve; what does it consist of?
In fact, there is nothing complicated in the design. A manual balancing valve is a valve-type device and usually consists of a body, an adjustment mechanism, the valve itself and two fittings, which are designed to measure the pressure before and after the control mechanism (thanks to them, the final flow rate of the medium in the area can be calculated). The adjustment occurs using a speed scale located on the adjustment mechanism (spindle). The automatic version of the valve additionally contains a differential pressure control cartridge, and the manual valve is replaced with a preset bandwidth.
There are many variations of valves on the market, so designs vary different manufacturers vary and may contain additional elements.
It looks like it's really simple. How to install balancing valves? Do they need to be somehow connected to the system?
They are usually used in one- and two-pipe heating systems and, if not included in the default design, are installed using special adapters and fittings. Installation of the structure can occur both horizontally and vertical position. It does not cause any particular difficulties: all the details are described in the instructions included in the kit. However, it is important to follow one rule: the arrow on the body of the balancing valve must coincide with the direction of movement of the coolant through the pipe (although some manufacturers make exceptions, providing the opportunity to install the valve against the flow).
When installing any valve, you should also adhere to general recommendations, which will simplify the process:
- will help prevent pipeline clogging strainer, installed in front of the valve;
- You can track the pressure level thanks to pressure gauges, which are recommended to be installed before and after the valve;
- the valve body must be free from excessive physical impacts and stress;
- to install the structure, it is important to choose a location that is accessible and convenient for maintenance;
- the valve must be placed on a straight section of the pipeline (the specific length of the straight sections before and after the valve is determined by the specific manufacturer in the instructions);
- Before installation, the pipeline must be flushed.
The installation principle is clear, now you need to select the appropriate valve. Which one is suitable?
When choosing a balancing valve, you need to take into account, first of all, the type of heating system. They are divided into dynamic and static . The first ones are used radiator thermostats, which automatically respond to the slightest changes in room temperature. This leads to the fact that the coolant flow is constantly changing. Designed for such systems automatic balancing valves, which are independently capable of maintaining the pressure level and stabilizing differences in the pipeline.
If the system is not equipped with automated pressure and media flow regulators, then it can be called static . Designed for such cases manual balancing valve. He, in turn, may be coupling or flange . The first one is connected to the system using internal thread, and the second - using bolts.
In addition, the choice also depends on the specific purpose and needs. Valves may differ in pressure and temperature parameters, throughput, installation location, type of connection, additional functionality and other criteria. It is important to calculate everything in advance required values and characteristics of the heating system in order to select the correct balancing valve.
Large multi-circuit systems heating systems quite often face the problem of uneven heating of different rooms. The coolant flows along the path of least resistance, which is why the farther from the heat source, the lower the consumption of thermal energy than next to it. A manual or automatic balancing valve for a heating system (otherwise known as a valve) is used to equalize the coolant flow in different branches.
The design of the radiator element, which serves for manual balancing of heating branches, consists of the following parts:
- A body with threaded pipes used to connect pipes, made of brass. Using casting, a so-called saddle is made inside, which is a round vertical channel that expands slightly upward.
- A shut-off and regulating spindle, the working part of which has the shape of a cone, which enters the saddle during twisting, thereby limiting the flow of water.
- O-rings made of EPDM rubber.
- Protective cap made of plastic or metal.
Everyone has famous manufacturers Products come in two types - angular and straight. Only the shape has changed, but the operating principle is the same.
How a valve works in a heating system: as the spindle rotates, the flow area decreases or increases, thereby making adjustments. The number of revolutions, from closed to open, to the maximum level varies from three to five revolutions, depending on who the manufacturer of the product is. To turn the rod, use a regular or special hexagon-shaped key.
Compared to radiator valves, main valves have a different size, an inclined position of the spindle, and excellent fittings, which are necessary for:
- to drain the coolant if necessary
- connecting metering and control devices;
- connecting the capillary tube coming from the pressure regulator.
It is also necessary to mention that not every system needs balancing as such. For example, 2-3 short dead-end branches, equipped with 2 radiators on each, can immediately enter normal operating mode, provided that the diameter of the pipes is selected accurately and the distances between the devices are not very large. Now let's look at 2 situations:
- There are 2-4 heating branches of unequal length leading from the boiler, the number of radiators on each is from 4 to 10.
- The same thing, only the radiators are equipped with thermostatic valves.
Since the bulk of the coolant always flows along the path with the least hydraulic resistance, in the first case, most of the heat will be received by the first radiators, which are closest to the boiler. If the flow of coolant to these batteries is not limited, then those standing at the very end of the batteries will receive the least amount of thermal energy, and thus the difference between temperature conditions will be from 10°C or more.
To ensure that the farthest batteries are provided required quantity coolant, balancing valves are installed on the connections to the nearest radiators from the boiler. By partially blocking the internal cross-section of the pipes, they limit the flow of water, thereby increasing the hydraulic resistance of this section. In a similar way, the supply is regulated in systems where there are 5 or more dead-end branches.
In the second case, the situation is somewhat more complicated. Installation of radiator thermostats makes it possible to change the water flow automatically if necessary. On long branches with big amount heating devices that are equipped with thermostats, balancing valves are combined with automatic differential pressure regulators.
The latter, using a capillary tube, are connected to a balance valve, react to a decrease or increase in coolant flow in the system and maintain the return pressure at the required level. Thus, the coolant is evenly distributed among consumers, despite the fact that the thermostats are activated.
What types of balancing valves are there?
Standard Ball Valves for heating radiators cannot cope with regulating the distribution of thermal energy in pipes and radiators. But nevertheless, in order to distribute heat evenly in the rooms, such adjustment is simply necessary.
There are two types of balancing valves - manual and automatic. Manual ones are necessary in order to configure the network during its installation, and automatic ones change the parameters of the heating network at the time of heating.
When selecting a valve, you need to take into account many characteristics, which include:
- type and characteristics of the coolant;
- installation location in the system;
- adjustment characteristics;
- adjustment parameters;
- classification of buildings;
The types of heating systems directly depend on the coolant they use. It can be antifreeze, steam, water. They directly affect the performance of the system.
Quite a lot important characteristic is the purpose of the system. The parameters of hot and cold water supply and heating systems differ quite greatly. For example, in DHW system Only thermostatic balancing valves are used.
The type of building where the balancing valve will be installed is of great importance. The installation location of the valve also plays a fairly important role, since the return and supply pipelines differ quite significantly from each other in characteristics. And because of this, the balancing devices that will be mounted on them will have significant differences.
Where and when is the main valve installed?
Most private homes use manual radiator valves. They are quite enough for normal adjustment of water heating in cottages whose area does not exceed more than 500 m². Installation Installation of main-type balancing valves in the heating system is done in the following cases:
- in buildings where an extensive heating network with a large number of risers is installed;
- in apartment buildings that are heated by their own boiler room;
- when tying solid fuel boiler with heat accumulator.
Once you have an idea of the purposes of balancing valves, you need to understand the specific locations of their installation. Radiator valves must be installed at the outlet of the heater, that is, on the return line, and main valves must be installed on the pipeline that brings cooled water from consumers to the boiler room. In the case when the element is paired with an automatic pressure regulator, it can be installed both in the return and supply pipelines, depending on how the circuit itself is designed.
Note: aluminum and steel radiators with a bottom connection are already equipped with a balancing tap, which is built into the special fittings that are necessary for connecting the connections to such devices.
We list the points in which it is not necessary to install control valves:
- in short-term dead-end systems, which have identical hydraulic “shoulders”;
- in the case when the batteries are equipped with thermostatic valves with presetting;
- in collector-type heating systems.
- on the last (dead-end) heating radiator;
Temperature regulators with presetting, which are installed on the water supply to the battery, also act as a balance valve, therefore it is necessary to install a shut-off ball valve at the outlet of the heating device. Such fittings are installed on the connections to the last radiator in the chain, since there is no particular point in adjusting it, and it must be completely open.
How to balance a heating system?
As a rule, heating system installers determine the coolant flow in the batteries quite simple method: the number of revolutions of the balancing valve is divided by the number of heating devices and thus the adjustment step is calculated. Moving from the last radiator to the first, the taps are tightened with the resulting speed difference.
For example, one arm of the dead-end system is equipped with 5 radiators with manual valves for 4.5 spindle turns. 4.5 must be divided by 5, as a result we get approximately 0.9 revolutions. And thus the penultimate device must be opened by 3.6 turns, the third by 2., the second by 1.8 and finally the very first by 0.9 turns.
The method is very approximate and takes into account different radiator powers, and is therefore used exclusively as a preliminary setting with adjustments during operation.
During installation, the following manipulations must be performed:
- check the system installation;
- in the place where the valve is to be installed, it is necessary to cut a thread;
- prepare the valve for installation;
- install the valve in its place in the system;
- A filter must be installed in front of the valve.
After the balancing valve is installed in the heating system, you need to begin the process of setting it up. This operation can only be performed by specialists, as it requires additional knowledge and equipment.
Step-by-step instructions for balancing can be presented as follows:
- All balancing valves must be opened to the limit and the system must be brought into operating mode, whose supply temperature will be 80°C.
- With help contact thermometer It is necessary to measure the temperature of all heating devices.
- In order to eliminate the resulting difference, it is necessary to close the taps of the first and middle batteries; there is no need to touch the end ones. The near heating radiator must be opened by 1-1.5 turns, and the middle ones by 2-2.5.
- The system will need about 20 minutes to adapt to the new settings, after which it is necessary to take measurements again. The main task is to achieve a minimum temperature difference between the nearest and farthest radiators.
Note. Weather and outside temperature do not matter, the only important characteristic is the difference in heating of the batteries.
Installation of balancing valves is necessary for large heating systems. They help to optimally distribute the coolant throughout all circuits. For such equipment correct work achieved correct installation and setting. The installation of valves should only be considered when designing the system.
To the owner of the house who is engaged in self-installation equipment for the heating system, you will certainly have to deal with balancing. It is quite easy to implement if all devices except the last one have balance valves.
The best choice would be models that can be easily adjusted with a screwdriver or wrench, rather than using plastic handle that children can reach. Perhaps in winter period you will have to adjust the position of the spindles, since heat loss in the rooms varies.
Advice: there is no need to make sudden movements, and open taps in cold rooms slowly by ¼ turn.