Several significant amendments were made to the federal law "On Heat Supply". Systems of closed and open heat supply

This is a system whose coolant is isolated and works exclusively for its intended purpose. It does not directly participate in the water supply, but only indirectly, it is not taken from the network by consumers. Let's just say that the "transfer" of heat for heating systems and for hot supply passes through heat exchangers. To do this, heat exchangers (heaters), pumps of various specializations, mixers, control equipment, etc. are installed in the heating units of buildings.

The list may vary depending on the type and capacity of the item. Central and individual heat points can have a different degree of automation, systems can be multi-stage and include several points on the way from the CHP to consumers. As a standard, with closed heat supply, the heat point has two circuits that ensure the transfer of heat to the heating system and the water supply system. Each circuit is equipped with a heat exchanger of the corresponding type, plate, multi-pass, etc. individually determines the project.

The liquid or antifreeze that transfers heat from the heat-preparation plant to secondary networks has a constant volume and can only be replenished by the feed system in case of losses. The coolant of the main line must undergo water treatment to give it required properties, ensuring harmlessness for network pipelines and heat exchange, both for heat points and heat-preparation facilities.

Coolant efficiency

The cycle passed by the heat carrier is a little more complicated than in an open mechanism. The cooled coolant, through the return line, enters the heating heaters or boiler rooms, where it receives the temperature from the hot process steam of turbines, condensate or is heated in the boiler. Losses, if any, are made up by the make-up liquid, thanks to the regulator. The device always maintains the set pressure, keeping its static value. If heat is received from CHP, the heat carrier is heated by steam having a temperature of 120° - 140°C.

The temperature is pressure dependent and sampling is usually done from medium pressure cylinders. Often there is only one heat extraction at the plant. The removed steam has a pressure of 0.12 - 0.25 MPa, which is increased (with controlled extraction) during seasonal cooling or steam consumption for aeration. When it gets cold, the liquid can be heated up by a peak boiler. An aerator can be connected to one of the turbine outlets, and chemically treated, treated water enters the feed tank. The heat removed for consumers, obtained from steam condensates and steam, is regulated qualitatively, that is, with a constant volume of the carrier, only the temperature is regulated.

Through the network pipeline, the coolant enters the heating unit, where the heating circuits form the required temperature. The water supply circuit does this with the help of a circulation line and a pump, having received water heated by a heat exchanger and mixing it with tap water and cooling water in the pipes. The heating one has its own control valves, which make it possible to qualitatively influence the heat extraction. The closed system assumes independent regulation of heat extraction.

However, such a scheme does not have sufficient flexibility and must have a productive pipeline. In order to reduce investments in the heating network, a coupled regulation is organized, in which the water supply flow regulator determines the balance in the direction of one of the circuits. As a result, the heating demand is compensated from the heating circuit.

The disadvantage of such balancing is a somewhat floating temperature of heated rooms. Regulations allow temperature fluctuations within 1 - 1.5 ° C, which usually occurs while maximum flow for water will not exceed 0.6 calculated, for heating. As in an open heating system, it is possible to use a combined quality regulation supply of heat. When the flow rate of the coolant and the heat transfer networks themselves are calculated for the load of the heating and ventilation system, increasing the temperature of the carrier to compensate for the need for hot supply. In such a case, the thermal inertia of buildings acts as heat accumulators, leveling out temperature fluctuations caused by uneven heat extraction from the connected system.

Advantages

Unfortunately, in the post-Soviet space, heat supply to the vast majority of consumers is still organized according to the old, open scheme. A closed scheme promises a significant gain in many ways. That is why the transition to closed heat supply, on a national scale can bring serious economic benefits. For example, in Russia, at the state level, the transition to more economical option, has become part of the energy saving program for the future.

Rejection old scheme will bring a reduction in heat loss, due to the possibility of precise adjustment of consumption. Each heat point has the ability to finely regulate heat consumption by subscribers.

Heating equipment operating in the isolated mode of a closed system is much less affected by the factors introduced by an open network. The consequence of this is an extended life of boilers, heat-preparation installations and intermediate communications.

It does not require increased resistance to high pressure, along the entire length of the heat-conducting mains, this significantly reduces the accident rate of pipelines due to pressure bursts. In turn, this reduces heat loss due to leaks. As a result, savings, stability and quality of heat and hot water compensate for the shortcomings of the system. And they also exist. Procedures cannot be carried out centrally. Each individual closed circuit requires its own maintenance. Be it turbines, subscriber circuits or an intermediate line.

Each heat station is a separate unit for water treatment. Most likely, when upgrading the circuit from open to closed, in most cases it will be necessary to increase the area required for installing ITP equipment, as well as reorganize the power supply. In addition, the consumption of cold water for supplying the building increases significantly, since it is it that is used for heating in heat exchangers and further to the consumer, with independent connection of hot water. This will invariably entail the reconstruction of the water supply, for the sake of switching to a closed hot circuit.

Global Introduction independent accession hot equipment to heating networks, will entail a significant increase in the load on external cold water supply networks, since it will be necessary to supply consumers with increased volumes necessary for hot water supply, which are now provided through heating networks. For many localities, this will become a serious obstacle to modernization. Additional equipment pumping units in hot supply and circulation installations, in building heating mechanisms will cause an additional load on Electricity of the net and without their reconstruction is also indispensable.

What is an open heating system, and how does it differ from a closed one? How is such a scheme implemented? How beneficial is it to the consumer? Let's try to figure it out.

Hello everybody

Let's start by introducing the participants and find out how open and closed systems differ:

• In the first case, water for hot water supply is taken from the heating system;

Only DH systems powered by combined heat and power plants or boiler houses are open. AT autonomous system DHW heating can use the same heat source (examples are a double-circuit boiler or boiler indirect heating), but the heating water is always taken from the cold water system.

• In the second case, the heating circuit is closed, and the entire volume of the coolant passing through it is returned for recirculation to the boiler house or CHP.

Implementation

Closed

How is a typical closed system heating supply in an apartment building?

The heating main is responsible for the delivery of the coolant to the house - two heat-insulated mains (supply and return) connecting the boiler room or CHP with consumers.

At each branch from the highway to a house or a group of houses, a thermal chamber is equipped with shut-off valves, vents and cranes for control measurements temperature and pressure.

Inside the house for the distribution of heat to consumers are responsible:

• Elevator node (heat point);

There may be several heating points in the house. Their number is determined mainly by the linear dimensions of the house: with in large numbers apartments and entrances, it is unprofitable to create one long circuit due to its high hydraulic resistance and the accompanying pressure loss.

• Supply and return spills (horizontal pipelines connecting the risers with the elevator unit);
• Risers that distribute the coolant to individual heaters.

Now - more about each element.

A heart elevator node- the so-called water jet elevator. It looks like a cast iron or (more rarely) steel tee with flanges for connection to the supply and return. A nozzle is located inside the elevator, which provides a dosed supply of water from the supply and its mixing with the coolant going for recirculation from the return pipeline.

Why is this needed?

Return water recycling allows:

• Increase the volume of coolant passing through the heating system per unit of time, with minimum flow water from the supply line of the heating main;
• Make more uniform heating of heating devices at the beginning and at the end of the circuit.

How does an elevator work?

Its operating principle is based on Bernoulli's law, which states that hydrostatic pressure in a liquid or gas flow is inversely proportional to the flow velocity. The supply water pressure exceeds the return pressure by 2-3 atmospheres. But after the nozzle, a rarefaction area is created, which draws part of the coolant from the return pipeline through suction.

The pressure difference between the mixture (water after the elevator) and the return flow is no more than 0.2 kgf/cm2.

The extreme extreme cold to maintain appropriate sanitary standards temperatures in apartments, the operation of an elevator without a nozzle is sometimes practiced. The suction is suppressed by a steel pancake mounted on the flange with a pair of rubber gaskets.

The coolant flow from the supply to the return is limited by adjusting the inlet valve on the return pipeline: it closes completely and then opens slightly with continuous monitoring of the pressure drop on the pressure gauge.

If you just close the valve, its cheeks can later slide down the stem and completely block the channel inside the body. The consequences of stopping circulation in extreme cold will not keep you waiting: during the first couple of hours, access heating will be defrosted, then accidents in apartments will follow.

The elevator needs a harness.

It consists of:

1. Entrance and house valves (two at the entrance to the elevator unit and two at the border between it and the actual heating circuit);

1. Mud collectors (at least one mud collector at the feed, in front of the elevator);
2. Control valves for measuring the pressure of the heat supply system;

Pressure gauges should be permanently installed in them, but due to massive thefts, representatives of the Heating Networks and housing organizations often forced to remove appliances.

1. Oil pockets for measuring temperature;
2. Dumps after house valves that cut off the circuit from the elevator unit (optionally with branch pipes that divert water to the sewer). They are needed to reset the heating system and to bypass it at startup: if you open one of the house valves and vent on the second line, most of the air will fly out through the vent.

Bottling heating is laid around the perimeter of the house.

It can be mounted in one of two ways:

1. The so-called top bottling means distributing the feed through the attic. The return outlet is located in the basement. The risers connecting them are turned off in two places - at the bottom and at the top;

This scheme complicates the shutdown of a single riser, but makes it easier to start a reset system. In order to start circulation in the circuit, it is enough to fill it and bleed air through a single air vent installed on the top point bottling supply expansion tank.

1. In the case of bottom filling, both the return and supply pipelines are routed through the basement or technical subfloor. The risers are connected to them in turn; each pair of risers top floor connected by a horizontal jumper, providing circulation.

Here the picture is reversed: it is somewhat easier to turn off a pair of risers, but when starting a reset circuit, you need to bleed air from each jumper. If the inhabitants of the upper apartments are chronically not at home, starting the riser can result in a serious problem.

Risers and eyeliners provide connection of heating devices. A typical nominal diameter of a heating riser is 20 - 25 mm, piping - 15-20. The connections to the devices are connected by jumpers, which ensure the operation of the riser with closed shut-off and throttling valves on them.

open

difference open circuit from closed - only in the fact that there are DHW tie-ins in the elevator unit.

In houses built before the mid-70s, the connection hot water implemented extremely simply: DHW filling is connected to the supply and return between the inlet valves and. Gate valves or valves are installed on the tie-ins; only one of the tie-ins is open at any given time, either supply or return.

Why do we need two independent tie-ins?

The fact is that at the peak of cold weather, the temperature of the supply line of the heating main at the outlet from the CHP can reach 150C. Water does not boil only thanks to overpressure. By supplying water directly from the heating network to consumers, it is easy to get a lot of accidents and domestic injuries.

On the return pipeline at the same time, the water temperature is quite acceptable 70 degrees.

In summer, the picture is different: there is no pressure drop in the route or it is minimal; the return temperature differs little from the ambient temperature. DHW needs are provided only by supply.

This scheme is extremely easy to maintain, but has a couple of serious drawbacks:

1. In the absence of water intake, the water in the pipes cools down. Accordingly, in the morning it has to be drained for a long time. This is at least inconvenient, and if there is a water meter for hot water supply, it is not at all comme il faut;
2. Towel warmers connected to the break in the hot water supply only heat up when you use hot water. Most time the bathroom is idle without heating.

In residential buildings of new projects, these problems have been successfully solved by a slight modernization of the scheme. DHW connections to the elevator node:

• Both on the supply and on the return, two DHW tie-ins are made between the inlet valves and the elevator;
• A retaining washer is installed on the flange between the tie-ins on each thread - a steel pancake with a hole 1 mm larger than the diameter of the elevator nozzle;
• There are two hot water outlets in the house;
• The risers are connected to them alternately and are connected on the top floor or in the attic with jumpers - just like on heating with a bottom filling.

The connection scheme of the risers can vary markedly. For example, a scheme is possible in which two risers with hot water pass through each apartment - the hot water supply itself and a riser with heated towel rails.

In the photo - hot water risers and heated towel rails in the basement of an apartment building.

Often, dryers are mounted in a riser gap, and risers are connected in 3-4 pieces - in groups corresponding to the number of apartments on the landing.

Depending on the season, the DHW system can operate in one of three modes:

1. In summer, outside the heating season, water circulates between the supply and return pipelines;
2. In the lower zone temperature graph two tie-ins in the feed are open. The pressure difference between them is provided by a retaining washer;
3. In severe cold, when the supply heats up over 90 degrees, the DHW is switched on from the return to the return. The difference is again created by a retaining washer.

Ratings

Which scheme is best for the consumer?

If the main criterion is water quality, there is no doubt. Heating with a boiler or a column is much more practical than supplying hot water from an elevator unit. The fact is that network water positioned as technical and intended only for household needs, but in cold water system served drinking water, corresponding to SanPiN 2.1.4.1074-01.

Another evaluation criterion is the price of a cubic meter of water. Let's do a simple calculation with our own hands - calculate the cost of a cubic meter of cold water heated by an electric boiler and compare it with the cost of a cube of hot water.

As a starting point, I will take the tariffs relevant at the beginning of 2017 for Moscow:

• A cubic meter of cold water without drainage costs 30 rubles;
• A cube of hot water costs 160 rubles;
• A kilowatt-hour of electricity at a one-part tariff is 5 rubles.

A few additional conditions:

• The average cold water temperature at the entrance to the house is approximately 15 degrees;
• target DHW temperature- 70 degrees;
• To simplify the calculations, I will neglect the heat loss of the boiler through thermal insulation, assuming its efficiency equal to 100%;

• It takes 1.1631 kilowatt-hours of heat to heat a cubic meter of water by 1C.

1. It will take 1.1631 * (70 - 15) = 64 (rounded) kilowatt-hours of electricity to heat up a cube of cold water to the target temperature;
2. Taking into account the cost of cold water and electricity tariffs, they will cost 64 * 5 + 30 = 350 rubles, which is more than two times the cost of a cubic meter of hot water.

The instruction is obvious: if you want to save on public services, use your own electric boiler definitely not worth it.

Conclusion

I hope that I was able to answer all the questions of the dear reader. The video in this article will help you learn more about heating and water supply schemes. I look forward to your additions to it. Good luck, comrades!

Heat supply is the supply of heat to residential, public and industrial buildings and structures to provide both domestic (heating, ventilation, hot water) and technological needs of consumers.

Heat supply is local and centralized. System district heating serves residential or industrial areas, and the local - one or more buildings. In Russia highest value acquired district heating.

Depending on the method of connecting the hot water supply system to the heat supply system, the latter is divided into open and closed.

Open heating systems

Open heat supply systems are characterized by the fact that hot water for the needs of the consumer is drawn directly from the heating network, and it can be either full or partial. The hot water remaining in the system continues to be used for heating or ventilation.

The water consumption in the heating network with this method is compensated by the additional amount of water that is supplied to the heating network. The advantage of an open heating system lies in its economic benefits. During Soviet period almost 50% of all heat supply systems were open.

At the same time, one cannot discount the fact that such a heat supply system also has a number of significant drawbacks. First of all, this is a low sanitary and hygienic quality of water. Heating devices and pipeline networks give the water a specific smell and color, various impurities appear, as well as bacteria. To purify water in an open system, they are usually used various methods, but their use reduces the economic effect.

An open heat supply system can be dependent on the method of connection to heat networks, i.e. connected through elevators and pumps, or connected according to an independent scheme - through heat exchangers. Let's dwell on this in more detail.

Dependent heating systems

Dependent heat supply systems are such systems in which the coolant through the pipeline enters immediately into the consumer's heating system. There are no intermediate heat exchangers, heating points and hydraulic isolation. Undoubtedly, such a connection scheme is understandable and structurally simple. It is easy to maintain and requires no additional equipment, For example, circulation pumps, automatic appliances regulation and control, heat exchangers, etc. Most often, this system attracts with its, at first glance, efficiency.

However, she has significant disadvantage, namely, the inability to adjust the heat supply at the beginning and end of the heating season, when there is an excess of heat. This not only affects the comfort of the consumer, but also leads to heat loss, which reduces its initial apparent efficiency.

When energy saving issues become relevant, methods are being developed and actively implemented for the transition of a dependent heat supply system to an independent one, this allows saving heat by about 10-40% per year.

Independent heating systems

Independent heat supply systems are systems in which the heating equipment of consumers is hydraulically isolated from the heat producer, and additional heat exchangers of central heating points are used to supply heat to consumers.

An independent heating system has a number of undeniable advantages. This is:

• the ability to control the amount of heat delivered to the consumer by regulating the secondary heat carrier;
• its higher reliability;
• energy-saving effect, with such a system, heat savings are 10-40%;
• it becomes possible to improve the operational and technical qualities of the coolant, which significantly increases the protection of boiler plants from pollution.

Thanks to these advantages, independent systems heat supply began to be actively used in major cities, where the heating networks are quite long and there is a large spread of thermal loads.

Currently, reconstruction technologies have been developed and are being successfully implemented. dependent systems into independents. Despite the significant investment, this eventually gives its effect. Naturally, an independent open system is more expensive, but it significantly improves water quality compared to a dependent one.

Closed heating systems

Closed heat supply systems are systems in which the water circulating in the pipeline is used only as a heat carrier and is not taken from the heat system for the needs of providing hot water. With this scheme, the system is completely closed from the environment.

Of course, coolant leaks are also possible with such a system, however, they are very small and easily eliminated, and water losses are automatically replenished without problems using the make-up regulator.

The heat supply in a closed heat supply system is regulated in a centralized way, while the amount of heat carrier, i.e. water remains unchanged in the system. The heat consumption in the system depends on the temperature of the circulating coolant.

As a rule, in closed heat supply systems, the capabilities of heat points are used. A heat carrier is supplied to them from a heat energy supplier, for example, a CHPP, and its temperature is regulated to the required value for the needs of heating and hot water supply by district central heating points, which distribute it to consumers.

Advantages and disadvantages of a closed heating system

The advantages of a closed heating system are high quality hot water supply. In addition, it gives an energy-saving effect.

Its, in fact, the only drawback is the complexity of water treatment due to the remoteness of heat points from each other.

Yekaterinburg will become an experimental platform for transferring an open hot water supply system to a closed circuit. The experience of the Ural capital will then be analyzed on federal level and transferred to other cities of Russia. According to preliminary data, the Ural metropolis will need about 10.6 billion rubles to modernize the network.

New DHW mode

Yekaterinburg will become a pilot site for a project of the Ministry of Energy of the Russian Federation: the city's heat and hot water supply system will be transferred from an open scheme to a closed one. This was reported in OJSC "Sverdlovsk Heat Supply Company" (STK, part of CJSC "Complex energy systems"). According to the Yekaterinburg Heat Supply Scheme (currently under development), the capital costs for transferring hot water supply to the new mode of operation are estimated at 10.6 billion rubles. However, this amount does not include the cost of rebuilding the water supply network. At the moment, the sources of financing have not been precisely defined either - according to the latest data, IES-Holding plans to invest approximately 30% of the declared cost, 70% of the financing is planned to be received from the state. Finally, the sources and ratio of funding will be determined by the beginning of 2015. The program is expected to be implemented by 2018. “Based on the experience gained in the Ural capital, they will work out a typical federal program, which is then broadcast to other Russian cities. Yekaterinburg was chosen because its heat supply system is one of the largest and most complex and is in dire need of modernization due to low production efficiency, big losses inside the networks and a shortage of reserves for connecting new facilities,” the STK explained.

As Aleksey Kozhemyako, Deputy Head of the Administration of Yekaterinburg for Housing and Communal Services, said, there are now working in Yekaterinburg different systems heat supply, "the city is one of the most complex in Russia in terms of the heat supply system." “One of the differences in Yekaterinburg is that it is one of the few cities where an open scheme was initially implemented. It is obvious that the city heating system needs to be modernized both in terms of current state, and in terms of perspective,” he said.

Return to pipe

As the Institute for Urban Economics notes, in Russia, open and closed DHW systems operate approximately on the same scale. The advantage of a closed circuit is the quality of hot water supplied to consumer taps. In an open circuit, hot water is often taken from heat sources. “In many cities of Russia, hot water is technical and not suitable for use, since, being a heat carrier for heating systems, it undergoes special chemical anti-corrosion preparation,” the Institute of Urban Economics reports. When transferring heat supply to a closed system, water for circulation in the heat network is not used for the needs of hot water supply and remains in the heat supply system. And through the DHW system, consumers will receive cold water (drinking quality), pre-heated with a heat exchanger to the desired temperature. According to the information of the fund, the transfer of the system to a closed scheme brings a number of economic benefits: in particular, the cost of chemical preparation of the heat carrier is reduced, since it is not required to take water from the heat supply system for supply to hot water supply.

Translation of the system is provided for by law. According to federal law No. 190, since the beginning of 2013 it is forbidden to connect objects capital construction with an open system. From 2022, take water from the coolant for DHW needs will be completely banned. As IES-Holding clarified, after the implementation of the project in Yekaterinburg, each municipality where the transfer of the system is required will develop its own individual program to change the heat supply scheme.

German calculation

In fact, work on the project will begin only after the completion of the heating season in 2014. At the moment, an audit is being carried out in Yekaterinburg to assess the scope of work and costs - for this purpose, IES has attracted the German Energy Agency Dena to the Sverdlovsk Region. In May 2013 Vitaly Anikin, Development Director of IES-Holding, and Stefan Kohler, Chairman of the Board of Dena, signed an agreement providing for the development of Yekaterinburg's heat supply system. “The contract provides for a technical audit of the city's heating network infrastructure, collection and systematization of initial data on the city's communal enterprises - MUE Ekaterinburgenergo and MUE Vodokanal,” the company explained. The specialists of the German agency, together with the Russian power engineers, will form the price and schedule for the implementation of the project. However, already within the framework of the agreement, representatives of the European company conducted an inspection of facilities in the Ural metropolis. Engineers inspected the Akademicheskaya CHPP under construction, the Gurzuf boiler house and the Novo-Sverdlovsk CHPP, as well as power facilities of the Sverdlovsk heating networks. The specialists were presented with general and hydraulic diagrams heat sources, pipelines and heat points of the city, as well as information on technical specifications heating systems.

Already at the end of June 2013, a series of meetings were held in Moscow at the central office of IES and the Ministry of Energy of the Russian Federation, where the reporting materials were considered. “CEC made a number of comments and suggestions to the materials provided. By the next meeting working group in the Ministry of Energy of the Russian Federation, approximately at the beginning of September 2013, it is planned to eliminate the comments to the contract and sign new contracts for the implementation of the next stages of the project,” IES-Holding emphasized.

hot time

It should be noted that as part of preparations for the 2018 FIFA World Cup in Yekaterinburg, a number of infrastructure projects are planned (their total cost, according to the Sverdlovsk government, is 124 billion rubles). According to the announced plans of the Russian Ministry of Sports, by 2018 it is planned to remove a number of objects from Repina Street, where the stadium is located. This list includes: the Ural Research Institute for the Protection of Motherhood and Infancy (NII OMM), the Ural State Medical Academy, SIZO-1 and correctional colony No. 2. In addition, it is planned to remove the polyclinic of the Federal State Institution “354 District Military Clinical Hospital” from Verkh-Isetsky Boulevard (located next to the stadium). Before the start of the Games, the transport infrastructure in the city must be reconstructed, water conduits modernized. “A 220 kV Nadezhda substation worth 3.2 billion rubles will be built in Yekaterinburg, more than 300 million rubles will be spent on the construction of loopback entrances,” said Valery, Director for Investments and Asset Maintenance of the branch of JSC FGC UES - Ural Power Grids Kurzhumov.

According to Investkafe analyst Ekaterina Shishko, the coordination of the IES-Holding project with other infrastructure programs may complicate the situation. “Some time will also be spent on coordinating the project with residents, since the cost of equipment installed in homes is likely to be financed by the population,” she notes. In connection with the modernization of the system, an increase in tariffs for housing and communal services is possible, since an increase in the cost of hot water supply may be required to reduce the payback period of the project. “However, the system itself promises many benefits and advantages for the residents of the city themselves. Also new system over time, it will reduce the cost of hot water and heating, which will positively affect the growth of tariffs, and in the long term, growth will either slow down or tend to zero,” the expert predicts. Ms. Shishko notes that Murmansk, Zelenograd and Nizhny Novgorod may become the next cities where the experience of transferring the open DHW system to a closed one will be duplicated. Also, the transfer of the system will be planned in Samara and St. Petersburg, the asset manager predicts financial company Aforex Sergey Kovzharov. “A number of projects are planned in Yekaterinburg, directly related to the preparations for the World Cup, so their implementation will be under strict control of the federal authorities. For this reason, we do not expect that the timing of the transfer of the heat supply system will be seriously shifted,” he said.

Specialists of the State Unitary Enterprise SO "Oblkommunenergo" warn their consumers about the upcoming cardinal changes in the legislation regulating heat supply. This was reported to UralPolit.Ru in the press service of the enterprise today, December 4th.

From January 1, 2013, amendments to the federal law of July 27, 2010 No. 190-FZ "On Heat Supply" will come into force. One of the most significant - addition to article 29 part 8:

8. From January 1, 2013, the connection of consumer capital construction facilities to centralized open heat supply systems (hot water supply) for the needs of hot water supply, carried out by taking the coolant for the needs of hot
water supply is not allowed.

Besides: addition to article 29 part 9:

9. From January 1, 2022, the use of centralized open heat supply systems (hot water supply) for the needs of hot
water supply, carried out by taking the coolant for the needs of hot water supply, is not allowed.

An open hot water supply scheme assumes that residents take hot water for their needs from the heat supply system, and a closed DHW system assumes the presence of special equipment for heating cold water and supplying it to residents at home as hot. The heating system works autonomously in this case.

Open analysis of hot water from the heating system has become a big problem and a headache for power engineers throughout Russia - today at least 70% of residential buildings supply hot water in this way.

Experts warn that the task set is truly revolutionary, large-scale and brings with it many related problems that will also need to be solved, but this has not yet been indicated by the legislator.

We present expert opinion about this deputy CEO State Unitary Enterprise SO "Oblkommunenergo" Evgeny Volkov:

In accordance with the amendments and additions made to the federal law No. 190-FZ of July 27, 2010 "On heat supply" (introduced by federal law No. 417-FZ of December 7, 2011), approaches to the creation of hot water supply systems will radically change . If earlier both systems, open and closed, had the right to exist, then from January 1, 2013, the connection of newly commissioned capital construction facilities to DHW systems should only be carried out closed scheme. And from January 1, 2022, open heating systems should disappear as a species, at least the authors of the law believe. Let us briefly recall what the types of heat supply systems are. An open heat supply system is when the coolant is used both for heating purposes and for hot water supply purposes. That is, hot water heating appliances and the faucet in the kitchen, in the bathroom - the same thing. A closed heat supply system assumes that the coolant circulates through closed loop, spending thermal energy only for heating. Hot water supply in this case is carried out by heating cold water with the same coolant, but through a heat exchanger. Let's try to compare the pros and cons of both systems and understand the idea behind the new legislation.

With an open system, the entire coolant undergoes mandatory water treatment at a heat source - a boiler house or a CHP. Cold water, before becoming a heat carrier, as a rule, requires a decrease in hardness in order to avoid scale formation when it is heated in boilers. In the absence of water treatment, hard water can disable an entire boiler room in a matter of months. Therefore, on any heat source, great attention is paid to the observance of the water-chemical regime. Reagents are spent on water treatment ( salt or sulfuric acid), electricity for water supply, routine maintenance of filters, funds are spent on the current operation and repair of equipment. With a closed scheme, all this will not happen, but who said that cold water for heating in the heat exchanger do not need to cook?

After all, if water has increased hardness, then when it is heated in the heat exchanger, intensive formation of hard-to-remove scale will also occur. That is, the solution to the problem of water treatment during the transition from an open to a closed circuit will move from generating facilities to consumers. But this will no longer be a single enlarged complex, but many small installations that will also need to be serviced, incurring the costs of reagents and maintenance personnel. At the same time, it is appropriate to recall the well-known rule - when a single whole is divided into several segments, the amount of costs increases. There is another factor - the level of maintenance of systems and equipment. It is impossible to compare the level of a plumber tightening nuts in the apartments of tenants, and complex system engineering support at large energy enterprises. It is unlikely that organizations serving internal systems buildings, will be able to ensure the proper level of operation of energy equipment (water treatment system, heat exchangers, automation to maintain the required water parameters).

The disadvantage of an open circuit is the so-called overheating. This means that during relatively warm periods, when the outdoor air temperature is close to zero or above zero, the heat supply company is forced to maintain the minimum temperature of the heat carrier at a level of at least 60 degrees, as required by SanPiN in terms of hot water quality requirements. But for heating systems, such temperatures are not required during warm periods. For example, at zero degrees outdoor temperature the coolant temperature indicator is 52 degrees. At plus 5 outside, the coolant temperature should already be 45 degrees, and at plus eight - 41 degrees.

The literature on the adjustment of heat supply systems mentions the so-called “cutting off” of the temperature graph according to the conditions of hot water supply. I.e minimum temperature 60 degrees is accepted for the coolant, and during the warm periods of the heating season (usually September, October, April, May), consumers receive much more heating than would be required by the standard. It should be noted that the requirements for hot water temperature for closed systems are somewhat softer: the required minimum temperature is 55 degrees. As a consequence, there is fuel savings compared to an open system, though. this is a relative circumstance - many heat supply organizations, looking at open windows in warm weather, already actually withstand temperatures in the region of 55-57 degrees.

A clear disadvantage of a closed system is the need to replace water supply networks. To date, the wear and tear of these networks is quite large, and many sections have undergone sanitation over the past 5-6 years ( polyethylene pipes), i.e. their diameter has decreased. The question arises before the water utilities - when switching to a closed system, it is necessary to increase throughput water networks almost twice. Given the above circumstances, an impressive volume of pipelines will have to be changed. But water tariffs are among the lowest and do not replace even the normative number of networks.

One of the options for a closed system is the supply of hot water from heat sources through a separate circuit (in Federal Law No. 190-FZ of July 27, 2010 “On Heat Supply”, oddly enough, only the concept of “open heat supply system” is formulated. There is nothing about a closed said, however, in some technical normative documents the term "closed system" is explained precisely in terms of installation heat exchangers at consumers. Therefore, whether the idea of ​​the author of these lines will have the right to exist is not yet clear). Nevertheless, to solve this problem, it is necessary to install again or separate from the existing boiler at the heat source, which will heat water only for the needs of domestic hot water. There is no need to "fence the garden" in the form of water treatment systems and heat exchangers for consumers, change water networks. But there is new problem: almost all heating networks will have to be shifted anew to create dedicated hot water pipelines. For example, if now heating network consists of two pipes (supply and return), then with a separate circuit, two more pipes must be added. In addition, it will be necessary to change the design of the network channels, since during their construction, as a rule, no one assumes an increase in the number of “threads” of pipelines, and where two pipes have already been laid in the tray, two more will obviously not fit. In a word - global replacement all heating networks. By the way, why not? The problem of wear and tear of networks is known, the loss of thermal energy exceeds all conceivable and unthinkable limits - it will be very convenient to kill not even two, but three or four birds with one stone with one shot. But the money for such modernization is unlikely to be found in the tariffs of heat supply organizations. And even the normative percentage of network replacement (4% per year) does not solve the problem within the prescribed period - until 2022. It takes at least 25 years, and then with the most favorable combination of circumstances and with the help of the state budget.

State Unitary Enterprise SO "Oblkommunenergo" is a backbone enterprise of the region's communal power industry, which carries out a comprehensive modernization of the housing and communal services of the Sverdlovsk region. Covering all areas of utility business (power grid business, heat supply, water disposal and water supply), Oblkommunenergo systematically solves the issues of development of the energy complex and engineering infrastructure 40 municipalities of the Sverdlovsk region.

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