Why is it hot in the kitchen and freezing in the bedroom? Adjusting heating radiators in the apartment. Self-regulation of the heating system: review of devices and techniques How to properly press down the return line on a heating system
If the system individual heating calculated correctly, no regulators are needed: a stable temperature will be maintained in each room. But in multi-storey buildings After a total heating overhaul, 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 corresponding values on the thermal head or closed the valve, and you have warm air, as much 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 ribs to increase heat transfer. The radiator input receives hot water, walking through the labyrinth, she heats the metal. This, in turn, heats the air around it. Due to the fact that modern radiators have fins special form, improving 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:
![](https://i1.wp.com/teplowood.ru/wp-content/uploads/2015/03/kak-regulirovat-temperaturu-8-600x450.jpg)
Main disadvantage regulated systems is that they need 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 absolutely inexpensive options, there are some that have a decent price. 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
Often at the entrance to the battery they place Ball Valves and with their help 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 flooring, and what will need to be repaired in the lower room depends on how quickly the workers close the riser utilities(or you, if you have own house). 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 reliability of the system 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 they have a needle tap 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 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 concerns quality products, the valve cone of which 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, others 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 control 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 firms bottom part radiator thermostat is made 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 general property: 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.
Watch the video to see how the thermostat works.
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 three-way valve head 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 is preferable and control valves. 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.
In the article we will touch on problems related to pressure and diagnosed with a pressure gauge. We will structure it in the form of answers to frequently asked questions. Not only the difference between the supply and return in the elevator unit will be discussed, but also the pressure drop in a closed-type heating system, the principle of operation expansion tank and much more.
Pressure - not less important parameter heating than temperature.
Central heating
How does an elevator unit work?
At the elevator entrance there are valves that cut it off from the heating main. Along their flanges closest to the wall of the house, there is a division of areas of responsibility between homeowners and heat suppliers. The second pair of valves cuts off the elevator from the house.
The supply pipe is always at the top, the return pipe is always at the bottom. The heart of the elevator unit is the mixing unit, in which the nozzle is located. A stream of hotter water from the supply pipe flows into the water from the return pipe, drawing it into a repeated circulation cycle through the heating circuit.
By adjusting the diameter of the hole in the nozzle, you can change the temperature of the mixture entering the.
Strictly speaking, an elevator is not a room with pipes, but this unit. In it, supply water is mixed with return water.
What is the difference between the supply and return pipelines of the route?
- In normal operation it is about 2-2.5 atmospheres. Typically, 6-7 kgf/cm2 enters the house on the supply side and 3.5-4.5 on the return side.
Please note: at the exit from the thermal power plant and boiler house the difference is greater. It is reduced both by losses due to the hydraulic resistance of the routes and by consumers, each of which is, simply put, a jumper between both pipes.
- During density tests, pumps pump at least 10 atmospheres into both pipelines. Tests are being carried out cold water when the input valves of all elevators connected to the route are closed.
What is the difference in the heating system
The difference on the highway and the difference in the heating system are two completely different things. If the return pressure before and after the elevator does not differ, then instead of supply, a mixture is supplied to the house, the pressure of which exceeds the readings of the pressure gauge on the return by only 0.2-0.3 kgf/cm2. This corresponds to a height difference of 2-3 meters.
This difference is spent to overcome the hydraulic resistance of bottlings, risers and heating devices. Resistance is determined by the diameter of the channels through which water moves.
What diameter should be the risers, fillers and connections to radiators in an apartment building?
The exact values are determined by hydraulic calculation.
In most modern houses the following sections are used:
- Heating outlets are made from pipes DN50 - DN80.
- For risers, a pipe DN20 - DN25 is used.
- The connection to the radiator is done either equal to the diameter riser, or one step thinner.
A caveat: you can only underestimate the diameter of the line relative to the riser when installing heating yourself if you have a jumper in front of the radiator. Moreover, it must be embedded into a thicker pipe.
The photo shows a more sensible solution. The diameter of the liner is not underestimated.
What to do if the return temperature is too low
In such cases:
- The nozzle is reamed. Its new diameter is agreed with the heat supplier. An increased diameter will not only increase the temperature of the mixture, it will also increase the drop. The circulation through the heating circuit will speed up.
- In the event of a catastrophic lack of heat, the elevator is disassembled, the nozzle is removed, and the suction (pipe connecting the supply to the return) is turned off.
The heating system receives water directly from the supply pipe. Temperature and pressure drop increase sharply.
Please note: this is an extreme measure that can only be taken if there is a risk of heating defrosting. For normal operation CHP and boiler houses have a fixed return temperature; By turning off the suction and removing the nozzle, we will raise it by at least 15-20 degrees.
What to do if the return temperature is too high
- The standard measure is to weld the nozzle and re-drill it, with a smaller diameter.
- When an urgent solution is needed without stopping the heating, the difference at the entrance to the elevator is reduced with the help of shut-off valves. This can be done with an inlet valve on the return line, monitoring the process with a pressure gauge.
This solution has three disadvantages:- The pressure in the heating system will increase. After all, we limit the outflow of water; the lower pressure in the system will become closer to the supply pressure.
- The wear of the cheeks and valve stem will accelerate sharply: they will be in a turbulent flow of hot water with suspensions.
- There is always the possibility of worn cheeks falling. If they completely shut off the water, the heating (primarily the access heating) will defrost within two to three hours.
Why do you need high pressure in the line?
Indeed, in private houses with autonomous systems For heating, an excess pressure of only 1.5 atmospheres is used. And, of course, more pressure means much higher costs for stronger pipes and power supply for injection pumps.
The need for greater pressure is associated with the number of floors in apartment buildings. Yes, circulation requires a minimum drop; but the water needs to be raised to the level of the jumper between the risers. Every atmosphere overpressure corresponds to a water column of 10 meters.
Knowing the pressure in the line, it is easy to calculate maximum height a house that can be heated without the use of additional pumps. The calculation instructions are simple: 10 meters multiplied by the return pressure. A return pipeline pressure of 4.5 kgf/cm2 corresponds to a water column of 45 meters, which, with a height of one floor of 3 meters, will give us 15 floors.
By the way, hot water supply in apartment buildings is supplied from the same elevator - from the supply (at a water temperature of no higher than 90 C) or return. If there is insufficient pressure, the upper floors will remain without water.
Heating system
Why do you need an expansion tank?
Accommodates excess expanded coolant when it is heated. Without an expansion tank, the pressure may exceed the tensile strength of the pipe. The tank consists of steel barrel and rubber membranes that separate air from water.
Air, unlike liquids, is highly compressible; with an increase in coolant volume by 5%, the pressure in the circuit due to the air tank will increase slightly.
The volume of the tank is usually taken approximately equal to 10% of the total volume of the heating system. The price of this device is low, so the purchase will not be ruinous.
The correct installation of the tank is with the hose facing up. Then excess air will not get into it.
Why does pressure decrease in a closed circuit?
Why does pressure drop in a closed heating system?
After all, the water has nowhere to go!
- If there are automatic air vents in the system, the air dissolved in the water at the time of filling will escape through them.
Yes, it makes up a small part of the coolant volume; but a large change in volume is not necessary for the pressure gauge to register the change. - Plastic and metal-plastic pipes May be slightly deformed under pressure. In combination with high temperature water this process will speed up.
- The pressure in the heating system drops when the temperature of the coolant decreases. Thermal expansion, remember?
- Finally, minor leaks are easy to see only in central heating along rusty tracks. Water in a closed circuit is not so rich in iron, and the pipes in a private house are most often not made of steel; therefore, it is almost impossible to see traces of small leaks if the water has time to evaporate.
Why is a pressure drop in a closed circuit dangerous?
Boiler failure. In older models without thermal control - up to an explosion. Modern older models often have automatic control of not only temperature, but also pressure: when it falls below a threshold value, the boiler reports a problem.
In any case, it is better to maintain the pressure in the circuit at a level of approximately one and a half atmospheres.
How to slow down the pressure drop
In order not to recharge the heating system over and over again every day, a simple measure will help: install a second expansion tank of a larger volume.
The internal volumes of several tanks are summed up; the greater the total amount of air in them, the smaller the pressure drop will cause a decrease in the volume of coolant by, say, 10 milliliters per day.
Where to put the expansion tank
Generally, big difference For membrane tank no: it can be connected anywhere in the circuit. Manufacturers, however, recommend connecting it where the water flow is as close to laminar as possible. If there is a tank in the system, the tank can be mounted on a straight section of pipe in front of it.
Conclusion
We hope that your question has not been left unanswered. If this is not the case, perhaps you can find the answer you need in the video at the end of the article. Warm winters!
Indoor comfort during the cold period largely depends on a correctly designed building heating system, in particular, on the choice of the organization of coolant supply and its outlet (return) in the heating system.
First of all, it should be noted that today there are two types of heating for homes:
- autonomous (independent) when thermal energy sources are located in a building or its immediate vicinity. This type is mainly used for individual construction projects or multi-storey buildings modern layout;
- centralized (dependent), in which several objects connected by a network of pipelines are connected to the heating device (or their complex). This system is typical for most urban residential areas, as well as villages with developed infrastructure.
At the same time, according to the principle of circulation of the coolant, which is most often used as water, there are gravitational(with natural circulation) and pumping(with forced circulation) heating systems, and according to the method of its distribution - with top or bottom piping layout.
Despite the diversity possible options providing buildings with heat, the number of ways to organize the supply and removal (return) of coolant is limited.
Methods for organizing the supply and removal of coolant to heating radiators
- lower;
- lateral;
- diagonal.
Bottom connection
In the literature you can find other names for this method: saddle, sickle, “Leningradka”. According to this scheme, both the coolant supply and return are provided at the bottom of the radiators. It is advisable to use it if the heating pipes are located under the floor surface or under the baseboard.
Legend:
1 – Mayevsky crane
2 – Heating radiators
3 – Heat flow direction
4 – Plug
It must be remembered that with a small number of sections or small size of radiators, the bottom connection is the least efficient in terms of heat transfer (heat loss can be 15%) than other existing schemes.
Side connection
This is the most common type of connecting radiators to a heating system. When using such a scheme, the coolant is supplied to the upper part, and the return is organized from the same side from the bottom.
It should be borne in mind that as the number of sections increases, the efficiency of such a connection decreases. To correct the situation, it is recommended to use a fluid flow extension (injection tube).
Diagonal connection
This scheme is also called a lateral cross scheme, since the coolant is supplied to the radiator from above, while the return is organized from below, but from the opposite side. It is advisable to provide such a connection when using radiators with a large number of sections (14 or more).
You need to know that when changing the location of the supply and return, the heat transfer efficiency is halved.
The choice of one or another option for connecting radiators will largely depend on the provided pipe layout (method of organizing return flow) in the heating system.
Methods for organizing return flow
Today, heating systems can be organized according to one of the types of pipe layout:
- single-pipe;
- two-pipe;
- hybrid.
The choice of one method or another will depend on a number of factors such as: number of floors of the building, requirements for the cost of the heating system, type of coolant circulation, radiator parameters, etc.
The most common is single-pipe scheme pipe routing. In most cases, it is used to heat multi-story buildings. Such a system is characterized by:
- low cost;
- ease of installation;
- vertical system with top coolant supply;
- serial connection of heating radiators, and, therefore, the absence of a separate riser for return, i.e. After passing through the first radiator, the coolant enters the second, then the third, etc.;
- inability to regulate the intensity and uniformity of heating of radiators;
- high coolant pressure in the system;
- decrease in heat transfer with distance from the boiler or expansion tank.
It should be noted that to increase the efficiency of single-pipe systems, it is possible to provide for the use of circular deposits or the installation of bypasses on each floor.
« Bypass- (English bypass, lit. - bypass) - a bypass parallel to a straight section of a pipeline, with shut-off or control pipeline valves or devices (for example, liquid or gas meters). Serves to control the technological process in the event of a malfunction of fittings or devices installed on a direct pipeline, as well as if they need to be urgently replaced due to a malfunction without stopping the technological process.” (Big Encyclopedic Polytechnic Dictionary)
Another option for pipe routing is two-pipe scheme , also called heating system with return. This type is most often used for individual construction projects or luxury housing.
This system consists of two closed circuits, one of which is designed to supply coolant to heating radiators connected in parallel, the second to remove it.
Main advantages two-pipe scheme are:
- uniform heating of all devices, regardless of their distance from the heat source;
- the ability to regulate the heating intensity or repair (replace) each of the radiators without affecting the operation of others.
TO shortcomings This can be attributed to a rather complex connection diagram and labor-intensive installation.
It must be taken into account that if such a system does not provide for the use of a circular pump, slopes should be observed during installation (for supply from the boiler, for return to the boiler).
The third type of pipe layout is considered hybrid , combining the characteristics of the systems described above. An example is a collector circuit, in which an individual wiring branch is organized from the common coolant supply riser at each level.
Return coolant heating
Obviously, the supply coolant temperature should be slightly higher than the return temperature. But the difference is quite large, which cannot be eliminated long time, leads to a reduction in the service life of boilers.
This is explained by the fact that condensate forms on the walls of the combustion chamber, which enters into a chemical interaction with carbon dioxide and other gases released during fuel combustion, forming an acid. Under its influence, the “water jacket” of the firebox gradually corrodes, and the boiler fails.
To eliminate this phenomenon, it is necessary to either heat the return coolant or provide for the inclusion of a boiler in the heating system.
Most of heating systems apartment and private houses were built precisely according to this scheme. What are its advantages and are there any disadvantages?
Can a two-pipe heating system be installed with one's own hands?
The difference between a two-pipe heating system and a single-pipe one
Let's first define what kind of beast this is - a two-pipe heating system. It’s easy to guess from the name that it uses exactly two pipes; but where do they lead and why are they needed?
The fact is that to heat a heating device with any coolant, it needs circulation. This can be achieved in one of two ways:
- Single-pipe circuit (so-called barracks type)
- Two-pipe heating.
In the first case, the entire heating system is one large ring. It can be opened by heating devices, or, which is much more reasonable, they can be placed parallel to the pipe; the main thing is that there is no separate supply and return pipeline passing through the heated room.
Or rather, in this case these functions are combined by the same pipe.
What do we gain and what do we lose in this case?
- Dignity: minimum costs materials.
- Disadvantage: large variation in coolant temperature between the radiators at the beginning and end of the ring.
The second scheme - two-pipe heating - is a little more complicated and more expensive. There are two pipelines running through the entire room (in the case of a multi-storey building - at least on one floor or in the basement) - supply and return.
First, the hot coolant (most often ordinary process water) goes to the heating devices to give them heat, and returns in the second direction.
Each heating device (or a riser with several heating devices) is placed in the gap between the supply and return.
There are two main consequences of this connection scheme:
- Disadvantage: the pipe consumption is much higher for two pipelines instead of one.
- Advantage: the ability to supply coolant to ALL heating devices at approximately the same temperature.
Tip: for each heating device in case large room It is necessary to install an adjustable throttle.
This will allow you to equalize the temperature more accurately, making sure that the flow of water from the supply to the return on nearby radiators will not “sag” those more distant from the boiler or elevator.
Features of two-pipe heating systems in apartment buildings
In the case of apartment buildings, of course, no one puts throttles on individual risers and regulates the water flow constantly; equalizing the temperature of the coolant at different distances from the elevator is achieved in another way: the supply and return pipelines running through the basement (the so-called heating bed) have a much larger diameter than the heating risers.
Alas, in new houses built after the collapse Soviet Union and the disappearance of strict state control over construction organizations, it began to be practiced to use pipes of approximately the same diameter on risers and benches, as well as thin-walled pipes installed for welding valves and other nice signs of the new social system.
The consequence of such savings is cold radiators in apartments located at the maximum distance from the elevator unit; By a funny coincidence, these apartments are usually corner and have a common wall with the street. Quite a cold wall.
However, we have deviated from the topic. Two-pipe heating system in apartment building has one more feature: for her normal functioning The water should circulate through the risers, rising and falling up and down. If something interferes with it, the riser with all the batteries remains cold.
What to do if the heating system at home is running, but the radiators are at room temperature?
- Make sure the riser valves are open.
- If all the flags and switches are in the “open” position, close one of the paired risers (we are, of course, talking about a house with, where both beds are in the basement) and open the vent located next to it.
If the water is flowing With normal pressure– there are no obstacles to the normal circulation of the riser, except for air at its upper points. Tip: drain more water until, after a long snorting of the air-water mixture, a powerful and stable stream of hot water flows. Perhaps in this case you will not need to go up to the top floor and bleed the air there - circulation will be restored after startup. - If the water does not flow, try to bypass the riser in the opposite direction: perhaps a piece of scale or slag is stuck somewhere. The countercurrent can carry it out.
- If all attempts have no effect and the riser does not drain, most likely you will have to search for a room in which repairs were made and heating appliances were changed. Here you can expect any trick: a removed and plugged radiator without a jumper, a completely cut off riser with plugs at both ends, a throttle closed for general reasons - again in the absence of a jumper... Human stupidity truly gives an idea of infinity.
Features of the top filling system
Another way to install a two-pipe heating system is the so-called top filling. What is the difference? The only problem is that the supply pipeline migrates to the attic or upper floor. Vertical pipe connects the filling bottling with the elevator.
Circulation from top to bottom; the path of water from supply to return with the same building height is half as long; all the air ends up not in the jumpers of the risers in apartments, but in a special expansion tank at the top of the supply pipeline.
Starting up such a heating system is immeasurably simpler: after all, for full operation of all heating risers, you do not need to go into every room on the top floor and bleed the air there.
It is more problematic to turn off the risers when repairs are necessary: after all, you need to both go down to the basement and go up to the attic. Shut-off valves are located both here and there.
However, the above two-pipe heating systems are still more typical for apartment buildings. What about private owners?
It’s worth starting with the fact that in private houses the 2-pipe heating system used can be radial and sequential according to the type of connection of heating devices.
- Radial: from the collector to each heating device there is its own supply and its own return.
- Sequential: radiators are powered by all heating devices from a common pair of pipelines.
The advantages of the first connection scheme boil down mainly to the fact that with such a connection there is no need to balance a two-pipe heating system - there is no need to adjust the flow of the throttles of the radiators located closer to the boiler. The temperature will be the same everywhere (of course, with at least approximately the same length of the rays).
Its main drawback is the most high consumption pipes among all possible schemes. In addition, it will simply be impossible to extend the lines to most of the radiators along the walls while maintaining any decent appearance: They will have to be hidden under the screed during construction.
You can, of course, drag it through the basement, but remember: in private houses there are often no basements of sufficient height with free access there. In addition, the beam scheme is in any way convenient to use only when building a one-story house.
What do we have in the second case?
Of course, we have gotten away from the main disadvantage of single-pipe heating. Coolant temperature in all heating devices theoretically it could be the same. The key word is theoretically.
Setting up the heating system
In order for everything to work exactly the way we want, we will need to configure a two-pipe heating system.
The setup procedure itself is extremely simple: you need to turn the throttles on the radiators, starting with those closest to the boiler, reducing the flow of water through them. The goal is to make sure that a decrease in water flow through nearby heating devices increases water consumption at distant ones.
The algorithm is simple: slightly tighten the valve and measure the temperature on the distant heating device. With a thermometer or by touch - in in this case all the same: the human hand perfectly feels a difference of five degrees, and we don’t need greater accuracy.
Alas, it is impossible to give a more accurate recipe other than “tighten and measure”: calculating the exact permeability for each throttle at each coolant temperature, and then adjusting it to achieve the required numbers is an unrealistic task.
Two points to consider when adjusting a two-pipe heating system:
- It takes a long time simply because after each change in the dynamics of the coolant, the temperature distribution takes a long time to stabilize.
- The heating adjustment of a two-pipe system must be carried out BEFORE the onset of cold weather. This will prevent you from defrosting your home heating system if you miss the settings.
Advice: with a small volume of coolant, you can use non-freezing coolants - the same as antifreeze or oil. It’s more expensive, but you can leave your house without heating in winter without worrying about the pipes and radiators.
Horizontal wiring system
With horizontal supply and return pipelines Lately from its patrimony – private and low-rise houses – it began to penetrate into multi-storey new buildings.
Apparently, this is largely due to the fact that studio apartments have begun to gain popularity: with a large area of the room without internal partitions, it is simply unprofitable to pull risers through the ceilings, as a 2-pipe vertical heating system implies; It is much easier to do the wiring horizontally.
Typical two-pipe horizontal heating system modern house it looks like this: the risers from the basement run along the entrance. On each floor, taps are made into the risers, which supply coolant to the apartment through valves and discharge waste water into the return pipeline.
Everything else is exactly like in a private house: two pipes, batteries and chokes on each of them. By the way, a horizontal heating system - two-pipe or one-pipe - is easier to repair: to dismantle and replace a section of pipe, there is no need to violate the integrity of the ceiling; This is undoubtedly worth recording as an advantage of such a scheme.
The horizontal two-pipe heating system has one feature that follows from its design and leaves its mark on the start of heating. In order for the heating device to transfer maximum heat from the coolant to the air in the room, it must be completely filled.
This means that each such heating device, typically located above the supply and return pipelines, must be equipped with a Mayevsky valve or any other vent in the upper part.
Advice: Mayevsky taps are very compact and aesthetically pleasing, but they are not the most convenient device for removing air from a radiator.
Where aesthetics are not important (for example, when heating devices are closed decorative grilles), it would be much more convenient to install a water tap with the spout up or a ball valve.
We will not add this feature to the list of disadvantages: going around the radiators in one apartment once a year is not a big deal.
As you can easily guess, a two-pipe horizontal heating system is not only a solution strictly for one-story buildings or for apartment buildings with studio apartments. For example, a two-story house with separate rooms can also be heated in the same way; you just have to make the wiring identical on both floors and connect pipelines from the boiler to both systems.
Of course, balancing such a heating system will have to take a little more time; but this is a one-time event, and it is not difficult to experience it once in a few years.
Finally, a few definitions and simply useful tips.
Depending on the direction of water flow in the pipelines, a 2-pipe heating system can be dead-end or direct-flow.
- A two-pipe dead-end heating system is a system in which the coolant moves through the supply and return pipelines in opposite directions.
- In a direct-flow two-pipe heating system, the direction of the current in both pipelines coincides.
In private houses, two-pipe heating systems with both forced and natural circulation can be used.
- Forced coolant circulation is ensured by circulation pump; This quiet and low-power device is supplied, in particular, in the same housing with many electric boilers.
- Natural circulation is used in small-volume heating systems; the principle of its operation is based on the fact that hot water has a lower density and rushes upward.
Two-pipe closed system heating, that is, a system with constant pressure and without both water supply and external coolant flow, is the most popular solution for private houses with electric boilers.
In order to transfer heat to distant rooms from a solid fuel boiler or stove, an open one-pipe or two-pipe system is quite suitable.
The design of a two-pipe heating system can include radiators of any type, registers and convectors as heating devices; warm floor implies a different connection method.
In order to install the heating of a two-pipe system, it is certainly better to involve specialists in the work. However, the abundance of materials on this topic on the Internet and the ease of assembling modern plumbing and heating systems with the help of fittings and machines make it possible for an amateur to do this work - if only he wanted to.
If you are installing a two-pipe heating system two-story house, when balancing the system, it is worth taking into account the peculiarity of communicating floors in terms of heat distribution: all other things being equal, it will always be warmer on the second floor.
Law of Hydraulics: Any flowing fluid chooses the path of least resistance. In the heating network of a private house, the rule works like this: the coolant pushed by the pump tends to pass through the first radiator or the shortest circuit of heated floors. As a result, remote rooms of the building warm up much worse. For uniform distribution of flows, hydraulic balancing of the heating system is necessary. We'll tell you how to adjust radiators and underfloor heating hinges with your own hands.
When to balance the system
Theoretically, adjustment of heating radiators is necessary in any case. Design engineer designing and calculating water system, sets the coolant flow rate for each radiator and underfloor heating circuit. After installation, filling and crimping pipeline network the contractor is obliged to adjust the heat supply, focusing on the design parameters in the project.
Important point. Calculation of heat demand and the corresponding consumption of heated water is done for the most unfavorable conditions - the minimum street temperature. Therefore, at the beginning of the settings, all radiator and other control valves are fully opened, and the boiler is brought to maximum operating mode.
Since the average homeowner only cares about the warmth and comfort inside the home, it is recommended that you take on the balancing yourself in the following cases:
- The radiators closest to the boiler heat up noticeably more than the radiators further away, respectively, the rooms are hot or cool (the temperature difference is too large).
- One of the radiators makes a distinct noise - the murmur of flowing water.
- Pipes embedded in the screed heat the floors unevenly.
- In the process of setting up a new heating circuit, assembled with your own hands.
Note. It is assumed that the fittings, equipment and heating devices are selected correctly, the system is filled with coolant, and there are no other defects. Otherwise, it is pointless to engage in hydraulic balancing - you will get zero results.
When you should not regulate the distribution of coolant to batteries:
- If the radiator network and heated floors work flawlessly. It’s not worth turning the valves over and over again - due to inexperience, you can make things worse.
- When various problems are detected - air in the batteries, leaks, clogged radiator or balancing valves, rupture of the expansion tank membrane, etc. First, fix the problem and check the heating is working properly. No adjustment may be needed.
- It is strictly not recommended to interfere with work central heating apartment building, install additional taps and valves into common risers. The exception is multi-storey new buildings with individual thermal inputs to each apartment.
![](https://i0.wp.com/otivent.com/wp-content/uploads/2018/06/Balansirovochnye-ventili-na-radiatorah-otoplenija.jpg)
Tools and devices for balancing
To independently adjust the heating radiators and heated floors of a private house, you will need a minimum of equipment:
- electronic contact thermometer;
- screwdriver;
- thumb or wrench to rotate the rod balancing valve(a hexagon is usually used);
- sheet of paper, pencil.
Reference. Professional plumbers often use a thermal imager, which gives a clear picture of the heating of all heating devices. The device is expensive, so we’ll make do with simpler means.
![](https://i1.wp.com/otivent.com/wp-content/uploads/2018/06/Pribor-dlja-balansirovki-otoplenija.jpg)
Instead of the specified thermometer, it is allowed to use a remote (non-contact) pyrometer. Please note: the device measures the temperature of shiny surfaces with a small error. This note applies to radiators with new paintwork.
If you do not have a wiring diagram for a residential building, you should sketch it on paper before starting work. The sketch will help you understand the order in which the batteries are connected to the mains and the distance from the furnace room. Also flush the mud trap at the entrance to the boiler and heat the system to a temperature of 70-80 °C, regardless of the street weather.
A great help in setting up is a modern circulation Grundfos pump Alpha 3, which accurately shows the depth of adjustments through the mobile application. The downside is the decent price of the unit (starts at 240 USD).
Radiator network adjustment
The balancing method practiced by our expert is equally suitable for closed one-pipe and two-pipe heating systems country cottages. Manifold wiring and heated floors are regulated in a different way, which we will discuss in the next section.
The essence of the technique is to measure the surface temperature of all radiators and eliminate the difference by limiting the coolant flow. How to adjust radiators using a thermometer:
- Warm up the coolant to 70-80 °C, open everything completely. If the boiler does not show the actual supply water temperature, determine it yourself by placing a meter on the metal outlet pipe.
Initially, the valve preset ring is adjusted to maximum flow
- Measure the surface temperature of the first radiator supply in two places - near the supply and return connections. If the difference is within 10 degrees, the battery warms up normally.
- Repeat the operation on all heating devices, recording the readings. Move along each heating branch, one by one recording the temperature of the batteries up to the last one.
- If the temperature difference between the supply of the first and last radiator does not exceed 2 °C, close the valves of the first two batteries by 0.5-1 turns and repeat the measurements.
The measurement is taken at the supply and return pipes, the maximum permissible difference is 10 degrees
- When the difference reaches 3-7 degrees, the control valves of the first heaters close by 50-70% (calculated by valve rotations), the middle ones - by 30-40%, the last devices remain completely open.
- Wait 20-30 minutes to allow the batteries to warm up after the new settings, then repeat the measurements. The goal is to achieve a normal difference of 2 °C (3 degrees is allowed for long highways) between the last and first device.
- Repeat the adjustment procedure, turning the balance valves a quarter or half a turn, until you achieve the same heating of all batteries. “Listen” to each radiator for noise indicating increased coolant consumption.
Important point. Don’t get carried away by excessively tightening the taps; you won’t get any savings this way. Compare the temperature at the inlet and outlet of the heater - if the difference exceeds 10 °C, the valve must be released. Due to too little coolant flow, the room will become cold.
Approximate adjustment of the batteries of a closed two-pipe system is shown using the example of a heating circuit for a two-story house. Why is it approximate: the number of batteries to be closed and the number of turns of the tap are purely individual for each wiring; it is necessary to understand it locally. If you doubt the correctness of your actions, press down the coolant gradually, making half a turn of the valve and repeating the measurements.
As a rule, a single-pipe “Leningrad” of 3-4 batteries does not need balancing; it is enough to lightly “press” the first radiator. In the associated wiring (), you need to limit the first and last device. An expert will show you the adjustment procedure more clearly in the video:
Warm floors and radiant wiring
Since the underfloor heating circuits and radiator radiators are connected to a common one, balancing is done directly on the collector. The setting method depends on the availability of rotameters - transparent flow meter flasks installed on the supply or return lines.
To correctly configure the coolant supply using rotameters, you should calculate the water flow through each loop using the formula:
- G – mass flow rate of heated water flowing through the circuit, kg/h;
- Q – the amount of heat that the circuit or radiator should release into the room, W;
- Δt – temperature difference at the inlet and outlet of the loop, the calculated value is taken to be 10 °C.
The power of one floor circuit Q is determined based on the heat demand of a separate room. The parameter is calculated according to the specific ratio of 100 W/m² of room area or according to the heating method. The flowmeter scales are marked in l/min, which means the result must be divided by 60.
Calculation example. Heating a room with an area of 10 square meters requires 1 kW of heat. Coolant consumption will be 0.86 x 1000 / 10 = 86 kg/h or 86 / 60 ≈ 1.43 l/min.
Clarification. If the room is large and has separate water loops, we also divide the calculated flow rate in half.
![](https://i0.wp.com/otivent.com/wp-content/uploads/2018/06/Balansirovka-kollektora-teplogo-pola.jpg)
Further balancing of underfloor heating loops is carried out according to the instructions:
![](https://i1.wp.com/otivent.com/wp-content/uploads/2018/06/Regulirovka-rotametrov-teplogo-pola.jpg)
Reference. On the collectors different manufacturers flow meters are installed on the supply or return manifold (they are also structurally different). To adjust the maximum flow, the location of the rotameters does not matter.
Beam batteries are balanced in a similar way. To be sure, you can combine 2 options - according to the calculated flow rate and the temperature of the radiator surface (the method is described in the previous section).
![](https://i0.wp.com/otivent.com/wp-content/uploads/2019/04/Ustrojstvo-rotametra-dlja-kollektora-TP.jpg)
If, in order to save money, you managed to buy a collector without rotameters, the setup will take several days. The goal is to achieve the same temperature in the return pipelines of all loops. That is, the initial installation is made approximately according to the power and length of the circuit, then the return temperature is measured and the flow rate is adjusted.
To check the balancing of the heated floor, you need to start the heating boiler. Negative point: after adjusting the flow rate, you will have to wait several hours until the thickness of the concrete warms up and the temperature of the return lines stabilizes.
Conclusion
A radiator heating network with short branches can be balanced without any problems. If the length of the arms of a two-pipe wiring varies greatly, the task becomes somewhat more complicated. But don’t worry - a difference of 3 degrees between the last and first radiator is considered normal in this case. Please note one nuance: heating balancing is carried out at maximum heating of the system; in operating mode, the water temperature will drop to 50...60 °C, the difference of 3 °C will also decrease.