Let's figure out how to regulate the temperature of the heating battery. Self-regulation of the heating system: review of devices and techniques Pressure drop and its importance for the functioning of the heating system

Any heating circuit operates at certain pressure and coolant temperature values, which are calculated at the design stage. However, during operation, situations are possible when the pressure drop in the heating system deviates from the standard level up or down and, as a rule, requires adjustment to ensure efficiency, and in some cases, safety.

Operating pressure in the heating system

Working pressure is considered to be the pressure whose value ensures optimal operation of all heating equipment (including the heating source, pump, expansion tank). In this case, it is taken equal to the sum of pressures:

• static - created by a column of water in the system (in calculations the ratio is taken: 1 atmosphere (0.1 MPa) per 10 meters);
• dynamic - due to the operation of the circulation pump and the convective movement of the coolant when it is heated.

It is clear that in different heating schemes the operating pressure will differ. So, if natural circulation of the coolant is provided for heating the house (applicable for individual low-rise construction), its value will exceed the static value by only a small amount. In forced schemes, it is taken as maximum permissible to ensure higher efficiency.

It should be borne in mind that the operating pressure limits are determined by the characteristics of the heating system elements. For example, when using cast iron radiators, it should not exceed 0.6 MPa.

Numerically, the working pressure is:

• for one-story buildings with an open layout and natural circulation of water – 0.1 MPa (1 atmosphere) for every 10 m of liquid column;
• for low-rise buildings with a closed layout - 0.2-0.4 MPa;
• for multi-storey buildings - up to 1 MPa.

Control of operating pressure in heating circuits

For normal, trouble-free operation of the heating system, it is necessary to regularly monitor the temperature and pressure of the coolant.

To check the latter, deformation pressure gauges with a Bourdon tube are usually used. To measure small pressures, their varieties can be used - diaphragm devices.

It must be remembered that after water hammer such models need to be verified, because they will show inflated values ​​in subsequent control measurements.

Figure 1 – Strain gauge with Bourdon tube

In systems where automatic control and regulation of pressure are provided, various types of sensors are additionally used (for example, electric contact).

The placement of pressure gauges (insertion points) are determined by regulations: devices must be installed in the most important areas of the system:

• at the inlet and outlet of the heating source;
• before and after the pump, filters, mud traps, pressure regulators (if any);
• at the exit of the main line from the thermal power plant or boiler house and at its entry into the building (with a centralized scheme).

You should not neglect these recommendations even when designing a small heating circuit using a low-power boiler, because This not only ensures the safety of the system, but also its efficiency due to optimal water and fuel consumption.

Figure 2 – Section of the heating circuit with installed pressure gauges

To make it possible to zero, purge and replace devices without stopping the system, it is recommended to connect them through three-way valves.

Pressure drop and its importance for the functioning of the heating system

For optimal functioning of any heating circuit, a stable and defined pressure drop is required, i.e. the difference between its values ​​at the coolant supply and return. As a rule, it should be 0.1-0.2 MPa.

If this indicator is less, this indicates a disruption in the movement of the coolant through the pipelines, as a result of which water passes through the radiators without heating them to the required degree.

If the difference exceeds the above value, we can talk about “stagnation” of the system, one of the reasons for which is airing.

It should be noted that sudden changes in pressure negatively affect the performance of individual elements of the heating circuit, often rendering them inoperable.

Methods for regulating operating pressure and ensuring the stability of its differential on the supply and return

1. First of all, it is necessary to remember that optimal operation of the heating system, incl. the creation of the required pressure in it depends on the correctness of the design, in particular, hydraulic calculations, and installation of mains and pipelines, namely:
   — the supply line in most schemes should be located at the top, the return line, respectively, at the bottom;
   — for the production of bottlings, pipes with a diameter of 50-80 mm should be used, for risers - 20-25 mm;
   — connections to heating devices can be made from the same pipes from which the risers are made, or one step smaller.

   It is allowed to underestimate the cross-section of radiator piping only if there is a jumper in front of them.

   

   Figure 3 – Jumper in front of the heating radiator

2. As you know, as the temperature rises, the coolant increases in volume and increases the pressure in the heating system. For example, at 20 0C it can increase by 0.13 MPa, at 70 0C - by 0.19 MPa. Therefore, one of the options for regulating the pressure is to change the degree of water heating.
3. To increase the coolant pressure, which is usually required to provide heat to the upper floors of high-rise buildings, circulation pumps are used.
4. Automatic regulation of operating pressure and its differential in heating circuits of small houses is carried out using expansion tanks, usually of the membrane type. They begin to work when the pressure in the system reaches 0.2 MPa. At the same time, these devices remove excess hot coolant, as a result of which the pressure is maintained at the required level.

   

   Figure 4 – Diaphragm expansion tank

   The expansion tank, the volume of which is usually taken to be about 10% of the total volume of the system, can be installed in any part of the circuit. However, experts recommend installing it on a straight section of the return pipeline in front of the circulation pump (if available).

   To prevent a situation where the device’s capacity is insufficient with a continued increase in pressure, the circuits provide for the use of a safety valve that removes excess coolant from the system.

5. In large and complex heating systems, for example, in multi-storey buildings, regulators are used to maintain the standard pressure, which additionally prevent airing even with sudden changes in pressure in the lines, as well as noise generation on the control valves. They are mounted either on a jumper between the supply and return pipelines, or on the bypass line of the pump.

   

   Figure 5 – Pressure regulator

6. Another way to regulate pressure in heat supply schemes of multi-level buildings is the use of shut-off valves. For example, if it is necessary to increase the pressure, the cross-section of the return pipeline is reduced using a valve.

Finding the reasons for the drop and increase in pressure drop

A deviation of pressure more or less from the norm requires establishing the cause of this phenomenon and eliminating it.

Pressure drop in the heating circuit

If the pressure in the heating system drops, then with a greater degree of probability we can talk about a coolant leak. The most vulnerable are the existing seams, joints and connections.

To check this, turn off the pump and monitor changes in static pressure. If the pressure continues to decrease, it is necessary to find the damaged area. To do this, it is recommended to sequentially disconnect different sections of the circuit, and after determining the exact location, repair or replace worn elements.

If the static pressure remains stable, the reason for the decrease in pressure is due to a malfunction of either the pump or the heating equipment.

It should be borne in mind that a short-term drop in pressure may be due to the peculiarity of the operation of the regulator, which at certain intervals transfers part of the water from the supply to the return. In the case when the heating radiators warm up evenly and to the required temperature, we can say that the difference was associated with the above cycle.

Other possible reasons include:

• removing air through vents, resulting in a decrease in the volume of coolant in the system;
• decrease in water temperature.

Increasing system pressure

A similar situation occurs when the movement of coolant in the heating circuit slows down or stops. The most likely reasons for this are:

• the occurrence of an air lock;
• contamination of filters and mud traps;
• features of the functioning of the pressure regulator or incorrect settings of its operation;
• constant replenishment of coolant due to automatic failure or incorrectly adjusted supply and return valves.

It should be noted that pressure instability is most often observed in newly launched systems and is associated with the gradual removal of air. This can be considered the norm if, after bringing the coolant volume and pressure to operating values, which lasts from several days to several weeks, no deviations are recorded.
Otherwise, we should talk about an incorrect hydraulic calculation, in particular, the accepted volume of the expansion tank.

If the individual heating system is designed correctly, no regulators will be needed: a stable temperature will be maintained in each room. But in multi-storey buildings after complete heating alterations, regulators can become very useful.

It is necessary to regulate the heat transfer of heating radiators for several reasons. First: it allows you to save on heating costs. In apartments in multi-storey buildings, payment bills will be reduced only if a common building heat meter is installed. In private homes, if you have an automated boiler that itself maintains a stable temperature, you are unlikely to need regulators for radiators. Unless you have old equipment. Then the savings will be quite significant.

The second reason why regulators are installed on heating radiators is the ability to maintain the temperature in the room that you want. You need +17 o C in one room, and +26 o C in the other, set the appropriate values ​​on the thermal head or close the valve, and you have as warm air as you want. It doesn’t matter whether you have radiators in your apartment, whether the coolant is supplied centrally, or whether the heating is individual. And it doesn’t matter at all what type of boiler is in the system. Radiator regulators are not connected in any way to boilers. They work on their own

How to regulate radiators

To understand how temperature regulation occurs, let’s remember how a heating radiator works. It is a labyrinth of pipes with different types of fins to increase heat transfer. Hot water enters the radiator inlet, passing through the labyrinth, it heats the metal. This, in turn, heats the air around it. Due to the fact that modern radiators have specially shaped fins that improve air movement (convection), hot air spreads very quickly. During active heating, there is a noticeable flow of heat from the radiators.

This battery is very hot. In this case, the regulator needs to be installed

From all this it follows that by changing the amount of coolant passing through the battery, you can change the temperature in the room (within certain limits). This is what the corresponding fittings do - control valves and thermostats.

Let's say right away that no regulators can increase heat transfer. They only lower it. If the room is hot, install it; if it’s cold, this is not your option.

How effectively the temperature of the batteries changes depends, firstly, on how the system is designed, whether there is a power reserve for the heating devices, and secondly, on how correctly the regulators themselves are selected and installed. The inertia of the system as a whole, and the heating devices themselves, plays a significant role. For example, aluminum heats up and cools down quickly, while cast iron, which has a large mass, changes temperature very slowly. So there is no point in changing anything with cast iron: it takes too long to wait for the result.

Options for connecting and installing control valves. But to be able to repair the radiator without stopping the system, you need to install a ball valve before the regulator (click on the picture to enlarge its size)

How to increase the heat dissipation of batteries

Whether it is possible to increase the heat transfer of a radiator depends on how it was calculated and whether there is a power reserve. If the radiator simply cannot produce more heat, then any means of adjustment will not help. But you can try to change the situation in one of the following ways:

The main disadvantage of adjustable systems is that they require a certain power reserve of all devices. And these are additional funds: each section costs money. But I don’t mind paying for comfort. If your room is hot, life is not a joy, just like if it is cold. And control valves are a universal way out of the situation.

There are many devices that can change the amount of coolant flowing through a heating device (radiator, register). There are very inexpensive options, and there are decent ones. Available with manual, automatic or electronic adjustment. Let's start with the cheapest ones.

Valves or taps

These are the most cost-effective, but, unfortunately, the most ineffective radiator adjustment devices.

Ball Valves

Ball valves are often installed at the entrance to the battery and with their help they regulate the flow of coolant. But this equipment has a different purpose: it is a shut-off valve. They are needed in the system, but to completely shut off the coolant flow. In the event, for example, if the heating device leaks. Then the ball valves located at the inlet and outlet of the heating radiator will allow it to be repaired or replaced without stopping the system and draining the coolant.

Ball valves are not intended for adjustment. They have only two operating states: completely “closed” and completely “open”. All intermediate positions cause harm.

Ball valves are shut-off valves and are not suitable for radiator adjustment

What harm? Inside this faucet there is a ball with a hole (hence the name - ball). In standard positions (open or closed), he is in no danger. But in other cases, the solid particles contained in the coolant (especially there are a lot of them in centralized heating systems) gradually grind down and break off pieces. As a result, the tap becomes leaky. Then, even if it is in the “closed” position, the coolant continues to flow into the radiator. And it’s good if an accident doesn’t happen at this time and you don’t need to turn off the water. But if this suddenly happens, repairs cannot be avoided. At a minimum, you will have to change the floor covering, and what will need to be repaired in the lower room depends on how quickly the utility workers (or you, if you have your own home) shut off the riser. Yes, a ball valve can work in abnormal mode for some time, but it still breaks. And sooner rather than later.

For those who still decide to adjust the radiator in this way, it is worth keeping in mind that they also need to be installed correctly, otherwise “pleasant” conversations with the management company cannot be avoided. Since this method is most often used in apartment buildings, we will tell you how to connect them with vertical wiring. Most often, the wiring is single-pipe vertical. This is when a pipe enters the room through the ceiling. A radiator is connected to it. The pipe leaves the second radiator inlet and goes through the floor to the lower room.

This is where you need to install the taps correctly: the mandatory installation of a bypass - a bypass pipe. It is needed so that when the flow to the radiators in the apartment is closed (the tap is closed completely or partially), water circulates in the general house system.

Sometimes the ball valve is placed on the bypass. By changing the amount of coolant passing through it, you can also change the heat transfer of the heating battery. In this case, for greater system reliability and the ability to turn off the taps, there should be three: two cut-off taps on the radiators, which will operate in normal modes, and a third one, which will be regulating. But there is one pitfall here: sometimes you can forget what position the taps are in, or the children will play. Result: the entire riser is blocked, cold in the apartments, unpleasant conversations with neighbors and the manager.

So It is better not to use ball valves for adjusting radiators. There are other devices designed specifically to change the amount of coolant flowing through the battery.

Needle valve

This device is usually installed in the heating system in front of the pressure gauge. In other places it does more harm than good. It's all about the structure. The device itself effectively and smoothly changes the flow of coolant, gradually blocking it.

But the thing is that due to the design features, The width of the passage for the coolant in them is half as large. For example, you have installed inch pipes and a needle valve of the same size. But its capacity is half as much: the saddle is only ½ inch. That is, each needle valve installed in the system reduces the throughput of the system. Several devices installed in series, for example, in a one-pipe system, will lead to the fact that the last heating devices either will not heat up at all, or will be barely warm. Therefore, the often recommended single-pipe circuit with needle valves in practice leads to the fact that most radiators either do not heat at all or heat very weakly.

• removing the needle valve;
• doubling the number of sections,
• by installing a device that has twice as large couplings (on inch pipes you will need to install a two-inch valve, which is unlikely to suit anyone).

Radiator control valves

Especially for manual adjustment of radiators intended radiator valves (taps). They come with corner or direct connection. The working principle of this manual temperature controller is as follows. By turning the valve, you lower or raise the shut-off cone. In the closed position, the cone completely blocks the flow. Moving up/down, it blocks the coolant flow to a greater or lesser extent. Because of this principle of operation, these devices are also called “mechanical temperature controllers”. It is installed on radiators with threads and connected to pipes using fittings, usually crimp fittings, but there are different types that are compatible with different types of pipes.

What is good about a radiator control valve? It is reliable, it is not afraid of blockages and small abrasive particles that are in the coolant. This applies to high-quality products whose valve cone is made of metal and carefully processed. Their prices are not very high, which is important for a large heating system. What's the disadvantage? Each time you have to change the position manually, which makes maintaining a stable temperature problematic. Some people are happy with this, some are not. For those who want a constant or strictly set temperature, they are more suitable

Automatic adjustment

Automatic maintenance of room temperature is good because once you set the regulator knob to the desired position, you will get rid of the need to twist and change something for a long time. The temperature of the heating radiators is adjusted constantly and continuously. The disadvantage of such systems is their significant cost, and the more functionality, the more expensive the device will be. There are some other features and subtleties, but more on them below.

Adjusting radiators with thermostats

For maintaining a constant set temperature in the room (premises) use thermostats or thermostats for heating radiators. Sometimes this device may be called a “thermostatic valve”, “thermostatic valve”, etc. There are many names, but one device is meant. To make it clearer, it is necessary to explain that the thermal valve and thermal valve are the lower part of the device, and the thermal head and thermoelement are the upper part. And the entire device is a radiator thermostat or thermostat.

Most of these devices do not require any power source. The exception is models with a digital screen: batteries are inserted into the thermostatic head. But their replacement period is quite long, the current consumption is low.

Structurally, the radiator thermostat consists of two parts:

• thermostatic valve (sometimes called “housing”, “thermal valve”, “thermal valve”);
• thermostatic head (also called “thermostatic element”, “thermoelement”, “thermal head”).

The valve itself (body) is made of metal, usually brass or bronze. Its design is similar to that of a manual valve. Most companies make the lower part of the radiator thermostat unified. That is, heads of any type and any manufacturer can be installed on one body. Let us clarify: you can install a manual, mechanical, or automatic thermocouple on one thermal valve. It is very comfortable. If you want to change the adjustment method, you do not need to buy the entire device. They installed another thermostatic element and that was it.

In automatic regulators, the principle of influencing the shut-off valve is different. In a manual regulator, its position is changed by turning the handle; in automatic models there is usually a bellows that presses on the spring-loaded mechanism. In electronic devices, everything is controlled by the processor.

The bellows is the main part of the thermal head (thermoelement). It is a small sealed cylinder containing liquid or gas. Both liquid and gas have one thing in common: their volume is highly dependent on temperature. When heated, they significantly increase their volume, stretching the bellows cylinder. It puts pressure on the spring, blocking the flow of coolant more strongly. As it cools, the volume of gas/liquid decreases, the spring rises, the coolant flow increases, and heating occurs again. This mechanism, depending on the calibration, allows you to maintain the set temperature with an accuracy of 1 o C.

How the thermostat works, watch the video.

The radiator thermostat can be:

• with manual temperature control;
• with automatic;
  • with built-in temperature sensor;
  • with remote (wired).

There are also special models for one-pipe and two-pipe systems, housings made of different metals.

Using Three-Way Valves

A three-way valve is rarely used to regulate battery temperature. He has a slightly different task. But in principle, it is possible.

A three-way valve is installed at the junction of the bypass and the supply pipe going to the radiator. To stabilize the temperature of the coolant, it must be equipped with a thermostatic head (of the type described above). If the temperature near the head of the three-way valve rises above the set value, the flow of coolant to the radiator is blocked. It all rushes through the bypass. After cooling, the valve operates in the opposite direction and the radiator heats up again. This connection method is implemented for, and more often with vertical wiring.

Results

Adjusting heating radiators is possible using different devices, but this must be done correctly using special control valves. These are manual regulators (taps) and automated ones - thermostats; in some versions it is possible to use a three-way valve with a thermal head.

In what case should I use what? In multi-storey apartments with central heating, a three-way valve and control taps are preferable. And all because the gap in thermostats for the coolant is not very wide, and if there are foreign particles in the coolant, it quickly becomes clogged. Therefore, they are recommended for use in individual heating systems.

If you really want automatic radiator control in your apartment, you can install a filter before the thermostat. It will retain most of the impurities, but you will have to wash it regularly. When you feel that the radiator has become too cold, check the filter.

In private houses with battery regulation, everything is simple: what suits you best, then install it.

What causes the pressure difference in heating and water supply systems? What is it for? How to regulate the difference? For what reasons does the pressure drop in the heating system? In this article we will try to answer these questions.

Functions

First, let's find out why the difference is created. Its main function is to ensure coolant circulation. Water will always move from a point with more pressure to a point with less pressure. The greater the difference, the greater the speed.

Useful: the limiting factor is the hydraulic resistance that increases with increasing flow velocity.

In addition, a difference is artificially created between the circulation taps of hot water supply in one thread (supply or return).

Circulation in this case performs two functions:

1. Provides consistently high temperatures for heated towel rails, which in all modern houses open one of the hot water supply risers connected in pairs.
2. Guarantees fast flow of hot water to the faucet regardless of the time of day and water supply through the riser. In old houses without circulation taps, water has to be drained for a long time in the morning before it is heated.

Finally, the difference is created by modern water and heat consumption meters.

How and why? To answer this question, the reader must be referred to Bernoulli's law, according to which the static pressure of a flow is inversely proportional to the speed of its movement.

This gives us the opportunity to design a device that records water flow without the use of unreliable impellers:

• We pass the flow through the section transition.
• We record the pressure in the narrow part of the meter and in the main pipe.

Knowing the pressures and diameters, using electronics it is possible to calculate the flow rate and water consumption in real time; when using temperature sensors at the input and output of the heating circuit, it is easy to calculate the amount of heat remaining in the heating system. At the same time, the consumption of hot water is calculated based on the difference in flow rates in the supply and return pipelines.

Creating a drop

How is pressure difference created?

Elevator

The main element of the heating system of an apartment building is the elevator unit. Its heart is the elevator itself - a nondescript cast-iron tube with three flanges and a nozzle inside. Before explaining the principle of operation of the elevator, it is worth mentioning one of the problems of central heating.

There is such a thing as a temperature graph - a table of the dependence of the temperatures of the supply and return routes on weather conditions. Let's give a short excerpt from it.

Deviations from the schedule up and down are equally undesirable. In the first case, it will be cold in the apartments, in the second, energy costs at the thermal power plant or boiler house will rise sharply.

At the same time, as is easy to see, the spread between the supply and return pipelines is quite large. With circulation slow enough for such a temperature delta, the temperature of the heating devices will be unevenly distributed. Residents of apartments whose radiators are connected to the supply risers will suffer from the heat, and owners of return radiators will freeze.

The elevator provides partial recirculation of the coolant from the return pipeline. By injecting a fast stream of hot water through the nozzle, in full compliance with Bernoulli's law, it creates a fast flow with low static pressure, which draws additional mass of water through the suction.

The temperature of the mixture is noticeably lower than that of the supply and slightly higher than that of the return pipeline. The circulation speed is high, and the temperature difference between the batteries is minimal.

Support washer

This simple device is a steel disk at least a millimeter thick with a hole drilled in it. It is placed on the flange of the elevator unit between the circulation taps. Washers are placed on both the supply and return pipelines.

Important: for normal operation of the elevator unit, the diameter of the holes in the retaining washers must be larger than the diameter of the nozzle.
Usually the difference is 1-2 millimeters.

Circulation pump

In autonomous heating systems, the pressure is created by one or more (according to the number of independent circuits) circulation pumps. The most common devices - with a wet rotor - are a design with a common shaft for the impeller and the rotor of the electric motor. The coolant performs the functions of cooling and lubrication of bearings.

Values

What is the pressure difference between different sections of the heating system?

• Between the supply and return lines of the heating main it is approximately 20 - 30 meters, or 2 - 3 kgf/cm2.

Reference: excess pressure of one atmosphere raises the water column to a height of 10 meters.

• The difference between the mixture after the elevator and the return pipeline is only 2 meters, or 0.2 kgf/cm2.
• The difference on the retaining washer between the circulation taps of the elevator unit rarely exceeds 1 meter.
• The pressure created by a circulation pump with a wet rotor usually varies from 2 to 6 meters (0.2 - 0.6 kgf/cm2).

Adjustment

How to adjust the pressure in the elevator unit?

Support washer

To be precise, in the case of a retaining washer, it is not necessary to adjust the pressure, but to periodically replace the washer with a similar one due to abrasive wear of a thin steel sheet in process water. How to replace the washer with your own hands?

The instructions are generally quite simple:

1. All gates or valves in the elevator are closed.
2. One drain valve is opened on the return and supply to drain the unit.
3. The bolts on the flange are loosened.
4. Instead of the old washer, a new one is installed, equipped with a pair of gaskets - one on each side.

Tip: in the absence of paronite, washers are cut from an old car inner tube.
Don't forget to cut an eyelet that will allow the washer to fit into the flange groove.

1. The bolts are tightened in pairs, crosswise. After the gaskets are pressed, the nuts are tightened until they stop, no more than half a turn at a time. If you rush, uneven compression will sooner or later lead to the gasket being torn out by the pressure on one side of the flange.

Heating system

The difference between the mixture and the return flow is normally regulated only by replacing, welding or drilling out the nozzle. However, sometimes it becomes necessary to remove the difference without stopping the heating (usually in case of serious deviations from the temperature schedule during the peak of cold weather).

This is done by adjusting the inlet valve on the return pipeline; Thus, we remove the difference between the forward and reverse threads and, accordingly, between the mixture and the return.

1. We measure the supply pressure after the inlet valve.
2. Switch the hot water supply to the supply thread.
3. We screw the pressure gauge into the vent on the return line.
4. We completely close the input check valve and then gradually open it until the difference decreases from the original by 0.2 kgf/cm2. Manipulation with the closing and subsequent opening of the valve is necessary to ensure that its cheeks are lowered as much as possible on the stem. If you simply close the valve, the cheeks may sag in the future; the price of ridiculous time savings is at least defrosted access heating.
5. The return pipe temperature is monitored at daily intervals. If it is necessary to further reduce it, the difference is removed 0.2 atmospheres at a time.

Pressure in the autonomous circuit

The immediate meaning of the word “difference” is a change in level, a fall. In the article we will touch on it too. So, why does the pressure drop in the heating system if it is a closed loop?

First, let's remember: water is practically incompressible.

Excessive pressure in the circuit is created due to two factors:

• The presence in the system of a membrane expansion tank with its air cushion.

• Elasticity. Their elasticity tends to zero, but with a significant area of ​​the inner surface of the circuit, this factor also affects the internal pressure.

From a practical point of view, this means that the pressure drop in the heating system recorded by the pressure gauge is usually caused by an extremely slight change in the volume of the circuit or a decrease in the amount of coolant.

Here's a possible list of both:

• When heated, polypropylene expands more than water. When starting a heating system assembled from polypropylene, the pressure in it may drop slightly.
• Many materials (including aluminum) are sufficiently plastic to change shape under prolonged exposure to moderate pressure. Aluminum radiators can simply swell over time.
• Gases dissolved in water gradually leave the circuit through the air vent, affecting the actual volume of water in it.
• Significant heating of the coolant when set too low can trigger the safety valve.

  The photo shows an intersectional leak on a cast iron radiator. Often it can only be noticed by traces of rust.

  Conclusion

  We hope that we were able to answer the reader’s questions. The video attached to the article, as usual, will offer additional thematic materials. Good luck!

Adjusting heating radiators in an apartment allows you to simultaneously solve several problems, the main one of which is to reduce the cost of paying for certain utilities.

This possibility is realized in different ways: mechanically and automatically. However, when changing the heating system parameters, the average room temperature does not increase. You can only reduce it to the desired level by adjusting the position of the fittings. It is advisable to install such devices on batteries in houses where it is cool in winter.

Why do you need to make adjustments?

The main factors explaining the need to change the heating level of batteries using locking mechanisms and electronics:

1. Free movement of hot water through pipes and inside radiators. Air pockets may form in the heating system. For this reason, the coolant stops heating the batteries, as it gradually cools. As a result, the indoor microclimate becomes less comfortable, and over time the room cools down. To maintain heat in the pipes, shut-off mechanisms installed on radiators are used.
2. Adjusting the temperature of the batteries makes it possible to reduce the cost of heating your home. If the rooms are too hot, by changing the position of the valves on the radiators you can reduce costs by 25%. Moreover, reducing the heating temperature of the batteries by 1°C provides savings of 6%.
3. In cases where radiators heat up the air in the apartment very much, you have to open the windows often. It is not advisable to do this in winter, because you can catch a cold. To avoid having to constantly open windows in order to normalize the microclimate in the room, regulators should be installed on the batteries.
4. It becomes possible to change the heating temperature of radiators at your discretion, and individual parameters are set in each room.

How to regulate radiators

To influence the microclimate in the apartment, you need to reduce the volume of coolant passing through the heating device. In this case, it is only possible to reduce the temperature value. The heating system is adjusted by turning the valve/faucet or changing the parameters of the automation unit. The amount of hot water passing through the pipes and sections is reduced, and at the same time the battery heats up less intensely.

To understand how these phenomena are interconnected, you need to learn more about the operating principle of the heating system, in particular, radiators: hot water entering the heating device heats the metal, which, in turn, releases heat into the air. However, the intensity of heating the room depends not only on the volume of hot water in the battery. The type of metal from which the heating device is made also plays an important role.

Cast iron has a significant mass and releases heat slowly. For this reason, it is not advisable to install regulators on such radiators, since the device will take a long time to cool. Aluminum, steel, copper - all these metals instantly heat up and cool down relatively quickly. Work on installing regulators should be carried out before the start of the heating season, when there is no coolant in the system.

In an apartment building, there is no way to change the average water temperature in the heating system pipes. For this reason, it is better to install regulators that allow you to influence the microclimate in the room in a different way. However, this cannot be realized if the coolant is supplied from top to bottom. In a private house there is access and the ability to change individual equipment parameters and coolant temperature. This means that in this case it is often impractical to mount regulators on batteries.

Valves and taps

Such fittings are a heat exchanger of a shut-off device. This means that the radiator is adjusted by turning the tap/valve in the desired direction. If you turn the fittings 90° all the way, the flow of water into the battery will no longer flow. To change the heating level of the heating device, the locking mechanism is set to the half position. However, not every fitting has this opportunity. Some faucets may leak after a short period of use in this position.

Installing shut-off valves allows you to regulate the heating system manually. The valve is inexpensive. This is the main advantage of such fittings. In addition, it is easy to operate, and changing the microclimate does not require special knowledge. However, there are also disadvantages to locking mechanisms, for example, they are characterized by a low level of efficiency. The battery cooling rate is slow.

Stopcocks

A ball design is used. First of all, it is customary to install them on a heating radiator in order to protect housing from coolant leakage. This type of valve has only two positions: open and closed. Its main task is to turn off the battery if such a need arises, for example, if there is a risk of flooding in the apartment. For this reason, shut-off valves are cut into the pipe in front of the radiator.

If the valve is in the open position, the coolant circulates freely throughout the heating system and inside the battery. Such taps are used if the room is hot. The batteries can be turned off periodically, which will reduce the air temperature in the room.

However, ball locking mechanisms must not be installed in the half position. With prolonged use, the risk of leakage in the area where the ball valve is located increases. This is due to gradual damage to the locking element in the form of a ball, which is located inside the mechanism.

Manual valves

This group includes two types of fittings:

1. Needle valve. Its advantage is the possibility of half installation. Such fittings can be located in any convenient position: completely opens/closes the access of coolant to the radiator, significantly or slightly reduces the volume of water in heating devices. However, there is a drawback to needle valves. Thus, they are characterized by reduced throughput. This means that after installing such fittings, even in a fully open position, the amount of coolant in the pipe at the battery inlet will be significantly reduced.
2. Control valves. They are designed specifically to change the heating temperature of batteries. The advantages include the ability to change the position at the user’s discretion. In addition, such fittings are reliable. There is no need to frequently repair the valve if the structural elements are made of durable metal. There is a shut-off cone inside the valve. When you turn the handle in different directions, it rises or falls, which helps to increase/decrease the flow area.

Automatic adjustment

The advantage of this method is that there is no need to constantly change the position of the valve/faucet. The desired temperature will be maintained automatically. Adjusting the heating in this way makes it possible to set the desired parameters once. In the future, the heating level of the battery will be maintained by an automation unit or other device installed at the input of the heating device.

If necessary, individual parameters can be set multiple times, which is influenced by the personal preferences of the residents. The disadvantages of this method include the significant cost of components. The more functional the devices are for controlling the amount of coolant in heating radiators, the higher their price.

Electronic thermostats

These devices superficially resemble a control valve, but there is a significant difference - a display is built into the design. It displays the room temperature that needs to be obtained. Such devices work in conjunction with a remote temperature sensor. It transmits information to the electronic thermostat. To normalize the microclimate in the room, you just need to set the desired temperature value on the device, and the adjustment will be performed automatically. Electronic thermostats are located at the battery input.

Adjusting radiators with thermostats

Devices of this type consist of two units: lower (thermal valve) and upper (thermal head). The first of the elements resembles a manual valve. It is made of durable metal. The advantage of such an element is the ability to install not only an automatic, but also a mechanical valve, it all depends on the needs of the user. To change the heating temperature of the battery, the design of the thermostat provides a bellows, which exerts pressure on the spring-loaded mechanism, and the latter, in turn, changes the flow area.

Using Three-Way Valves

Such devices are made in the form of a tee and are intended for installation at the connection point of the bypass, the inlet pipe to the radiator, or the general riser of the heating system. To increase operating efficiency, the three-way valve is equipped with a thermostatic head, the same as that of the previously discussed thermostat. If the temperature at the valve inlet is higher than the desired value, the coolant does not enter the battery. Hot water is directed through the bypass and passes further along the heating riser.

When the valve cools down, the passage hole opens again and the coolant flows into the battery. It is advisable to install such a device if the heating system is single-pipe and the pipe distribution is vertical.

To be able to regulate the temperature of the battery in the apartment, consider any type of valve: they can be straight or angular. The installation principle of such a device is simple; the main thing is to correctly determine its position. Thus, the direction of coolant flow is indicated on the valve body. It must correspond to the direction of water movement inside the battery.

Place valves/thermostats at the inlet of the heating device; if necessary, install a tap at the outlet as well. This is done so that in the future it will be possible to independently drain the coolant. Regulating devices are installed on radiators, provided that the user knows exactly which pipe is the supply pipe, since a tap is made into it. In this case, the direction of movement of hot water in the riser is taken into account: from top to bottom or from bottom to top.

Compression fittings are more reliable, which is why they are used more often. The connection to the pipes is threaded. Thermostats can be equipped with a union nut. To seal the threaded connection, use FUM tape or flax.

When designing heating systems, professional craftsmen must include special technical means in them, which in the future will allow them to control the pressure and temperature in the network. Such means are shut-off valves and other devices. We will talk about the rules and features of adjusting heat supply systems in this article.

Adjusting heat supply - what methods to use?

During heating operation, the coolant in the system heats up and expands, that is, it increases in volume. That is why the owner sometimes needs to adjust the heating radiators in his private home, thereby controlling the operation of the heating supply. There are several types of devices that allow you to do this kind of work. All devices are usually divided into two categories:

1. 1. regulatory;
2. 2. controlling.

The first allow you to regulate the pressure and temperature in the system, and reduce these parameters up or down. They can be installed on individual sections of the pipeline and used to regulate individual parts of the network, or regulate the operation of the entire system as a whole. Control devices are all kinds of thermometers and pressure gauges installed separately from the control means in the systems or together with them. They allow you to obtain information about the operation of the heating supply at any time and make a decision about the need to configure it.

To ensure that no difficulties arise with its adjustment during heating operation, when designing engineering it is necessary to provide for:

• installation of thermometers and pressure gauges before and after the heating boiler, in distribution manifolds (in the lowest and highest parts of the network);
• installing a pressure gauge before the circulation pump, if present in the system;
• installation of an expansion tank: leaky - in open networks and membrane - in closed ones;
• installation of safety valves and air vents necessary to prevent pressure in pipes from increasing to critical values.

During normal operation of the system, the water temperature in the pipes should not exceed 90 degrees, and the pressure should be within 1.5-3 atmospheres. Some heating networks can operate at higher temperatures and pressures, but they use special elements not found in standard home heating systems. The inability to regulate the battery with a conventional thermostat may indicate the formation of an air lock. To eliminate it, you will have to use the Mayevsky crane.

How to set up heating in a private house - features and nuances

The heating networks of private houses and apartment buildings vary greatly. In a separate residential building, the operation of the heat supply can only be affected by internal factors - problems with autonomous heating, but not breakdowns in the overall system. Most often, problems arise due to the boiler, the operation of which is affected by its power and the type of fuel used.

Heating settings

The possibilities and methods of adjusting home heating depend on several factors, the most significant of which are the following:

1. 1. Material and diameter of pipes. The larger the cross-section of the pipeline, the faster the heating and expansion of the coolant occurs.
2. 2. Features of radiators. Radiators can be adjusted normally only if they are properly connected to the pipes. If installed correctly, during operation of the system it will be possible to control the speed and volume of water passing through the device.
3. 3. Availability of mixing units. Mixing units in two-pipe systems make it possible to reduce the temperature of the coolant by mixing cold and hot water flows.

The installation of mechanisms that allow comfortable and sensitive regulation of pressure and temperature in the system must be provided for at the design stages of a new autonomous communication. If you install such equipment without preliminary calculations into an already functioning system, its efficiency can significantly decrease.

Ways to stabilize pressure in a home system

When the coolant is heated, it increases significantly in volume, but because of this, the pressure in the network can greatly jump, exceeding all possible critical values, which leads to the most unpleasant consequences. Expansion tanks are often used to regulate pressure in systems. A tank is a container divided into two chambers, one of which is filled with water from the heating network, and air is pumped into the other. In the air chamber, the air pressure is equal to the normal pressure in the heating pipes, therefore, if the pressure in the system increases above normal, a special membrane increases the volume of the water chamber, compensating for the expansion of the liquid in the pipes.

Before adjusting the pressure, it is necessary to check the settings and general condition of the expansion tank. You can simply change the pressure if your system has a tank that allows you to set the pressure in the air chamber. To make it easier to control the pressure, you can also install a pressure gauge. However, in the event of a sharp surge in pressure in the network, one expansion tank will not be enough to stabilize it, so experts recommend using additional devices.

To regulate the pressure in the heating network at any, even critical values, you can use a special safety group. It includes a whole set of useful devices:

1. 1. A pressure gauge that allows you to visually monitor the operation of the network.
2. 2. An air vent with a valve through which excess air leaves the pipes when the coolant temperature reaches 100 degrees.
3. 3. A safety valve, which, when the system reaches critical characteristics, will automatically drain excess water from the pipes.

The safety unit is needed to prevent accidents in the system as a whole; it cannot be used to regulate individual elements (radiators) of the heating supply of an apartment or private house. To regulate the condition of the batteries, it is necessary to use another device, namely the Mayevsky tap. In its design, such a valve is very similar to a safety valve, but is small in size and can be installed on a radiator pipe of even small diameter. The Mayevsky crane can be used in the following cases:

1. 1. If air pockets occur in the batteries. By opening the tap, you can slowly drain excess air from the radiator and close the valve as soon as water starts flowing from the tap.
2. 2. At high pressure in the radiator. In the event of emergency expansion of the coolant due to high pressure, you can open the valve and stabilize the pressure in the system.

Despite the possibility of using the Mayevsky valve to stabilize pressure, it is used for these purposes very rarely. It is much easier and more effective to use a special security group, but if you don’t have one, you can use this simple tool.

Heating problems - we monitor the water temperature in the network

An equally important characteristic of the operation of the heating network is the temperature of the coolant. In two-pipe systems, the optimal temperature characteristics of the hot and cooled coolant are the ratio of 75/50 degrees or 80/60 degrees. To easily regulate the temperature, you will have to install special equipment and elements in the system.

The easiest way is to create mixing nodes in the network. A mandatory element of such units are two- and three-way valves. One pipe of the mixing unit is connected to a pipe with hot water, and the second to a pipe with cold water. The third pipe is installed on the section of the line in which it is necessary to ensure a decrease in the temperature of the liquid, if such a need arises.

To simplify the use of mixing units, they are equipped with temperature sensors and a special thermostatic control unit. The sensor can send a signal about the temperature of the coolant and, based on the temperature level, close or open the mixing valve to regulate the heating. Typically, such equipment is installed in underfloor heating manifolds. To effectively regulate the water temperature in the heating of an apartment building, it is necessary to take into account the temperature regime in the pipes; usually the temperature of the pipes in the apartment does not exceed 45 degrees.

To reduce the water temperature in the pipes of an apartment building, you can use special shut-off valves. Sometimes it is enough to install simple taps that regulate the flow of coolant into the radiators, but in this case you will have to control the heating of the room yourself. It is much easier to regulate the heat supply using servos.

Servo drive is a device whose design includes a drive control unit and a thermostat. To ensure that the temperature in the rooms is always maintained at the same level, you need to set the desired value on the thermostat, and the servo drive will automatically open and close the flow of coolant to the radiator. To reduce repair costs, you can simply purchase a model with only a thermostat. But in this case, the adjustment will not be as accurate.

To regulate the temperature in apartments with old heating systems and cast iron radiators, it is necessary to use special thermostats. These devices, however, do not allow changing the pressure in the pipes; for this purpose, specialized means must be used.

The devices and methods for adjusting the heating system described above significantly increase the efficiency and safety of its operation. It would be useful for the owner to know the rules for installing some individual network elements that directly affect the quality of its functioning. Battery adjustment begins at the design stages of a new communication and during the installation process. It is important to choose the right method for connecting radiators, since the type of installation directly affects the efficiency of the device and the further possibility of installing special thermostats.

If you want to monitor and regulate the operation of equipment, you must take into account the pipe layout. In single-pipe systems, there is always a jumper or bypass necessary to redirect the flow of hot water in the event of radiator replacement and other repairs. In two-pipe networks, heating elements are connected in parallel to each other, so it is much easier to regulate the temperature of the batteries.

In a private house, during any heating work, it is necessary to take into account the characteristics and individual characteristics of the installed boiler. The efficiency of the engineering system depends on it. To ensure that the network works correctly and can be easily adjusted, choose a boiler taking into account:

1. 1. Rated power. For 10 m 2 of area, about 1 kW of boiler power is required with minimal heat losses.
2. 2. Ratio of heating boiler power to water volume. To heat 15 liters of coolant, 1 kW of power is needed.
3. 3. Permissibility of smooth regulation of the boiler. Typically, gas boilers have this function.

If you and the hired designers manage to correctly calculate the required boiler parameters, during operation of the heating network it will be possible to regulate the water temperature in the radiators as simply and accurately as possible. A good boiler increases the safety of home engineering and makes the network more reliable and functional. Do not forget to take into account the climatic conditions in your region when making calculations. In the northern regions of Russia, more powerful boilers are required, and in the southern regions, less powerful ones, which make it possible to spend much less money and resources to maintain comfortable temperature conditions in the rooms.