Water supply of an apartment building scheme. Housing and communal services in Russia

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The constant supply of hot water to an apartment building can be carried out by two methods using different principles of operation:

In the first case, the hot water supply of an apartment building takes water from the cold water pipeline (cold water supply), then the water is heated by an autonomous heat generator: an apartment boiler, a gas water heater or a boiler, a heat exchanger that uses the heat of a local stoker or CHP;
In the second case, the hot water supply scheme of an apartment building takes hot water directly from the heating main, and this principle is used in the residential sector much more often - in 90% of cases of organizing hot water supply in the housing stock.

Important: the advantage of the second version of the water supply system for a residential building is the best water quality, which is regulated by GOST R 51232-98. Also, when hot water is taken from a centralized heating main, the temperature and pressure of the liquid are quite stable and do not deviate from the specified parameters: the pressure in the pipeline of the hot water supply system is maintained at the level of cold water supply, and the temperature stabilizes in the common heat generator.

Let us consider the water supply of an apartment building according to the second option in more detail, since it is this scheme that is most often used both in the city and in country houses, including country houses or garden houses.

What elements does the water supply scheme of an apartment building include?

The water meter unit, which organizes the supply of water to the house, is responsible for the operation of several functions:

Takes into account the consumption of cold water supply, that is, it performs the function of a water meter;
It can shut off the supply of cold water to the house in case of emergency or if it is necessary to repair components and parts, as well as to eliminate leaks;
It serves as a coarse water filter: any hot water supply scheme of an apartment building should contain such a mud filter.

The device itself consists of the following nodes:

A set of shut-off valves (faucets, gate valves and gates) at the inlet and outlet of the device. Standardly these are gate valves, ball valves, valves;
Mechanical water meter, which is installed on one of the risers;
Mud filter (coarse water filter from large solid particles). This may be a metal mesh in the body, or a container in which solid debris settles to the bottom;
Pressure gauge or adapter for inserting a pressure gauge into the water supply circuit;
Bypass (bypass from a pipe section), which serves to turn off the water meter during repairs or reconciliation of data. The bypass is supplied with shut-off valves in the form of a ball valve or valve.

It is also an elevator unit that performs the following functions:

Ensures the full and continuous operation of the heating system in an apartment building, and also regulates its parameters;
Delivers hot water to the house, that is, provides hot water supply (hot water supply). The coolant itself in the heating system enters the hot water supply system of an apartment building straight from the centralized heating main;
The substation can switch the hot water supply between return and supply. This is sometimes necessary during severe frosts, since at this time the temperature of the coolant in the supply pipe can rise to 130-150 0 С, and this despite the fact that the standard supply temperature should not exceed 750С.

The main element of the heating point is a water-jet elevator, where hot water from the pipeline scheme for supplying the working fluid in the house is mixed in the mixing chamber with the return coolant by injection through a special nozzle. Thus, the elevator allows a larger volume of coolant with a low temperature to pass through the heating circuit, and, since the injection is performed through a nozzle, the supply volume is small.

It is possible to insert adapters for connecting hot water supply between the valves at the entrance of the route and the heat point - this is the most common connection scheme. The number of tie-ins - two or four (one or two on the supply and return). Two tie-ins are typical for old houses, four adapters are practiced in new buildings.

On the cold water route, a dead-end tie-in scheme with two connections is usually used: the water metering unit is connected to the bottling, and the bottling itself is connected to the risers through which the pipes are routed to the apartments. Water will move in such a cold water circuit only when disassembled, that is, when any mixers, taps, valves or gates are opened.

Disadvantages of this connection:

With a long absence of water intake for a specific riser, the water will be cold for a long time when draining;
Heated towel rails embedded on the hot water supply from the boiler rooms, which simultaneously heat the bathroom or bathroom, will be hot only when the hot water supply is drawn from a specific riser of the apartment. That is, they will almost always be cold, which will cause moisture to appear on the walls, mold or fungal diseases of the building materials of the room.

The heating station with four hot water connections in the house makes the circulation of hot water continuous, and this happens through two fillings and risers connected to each other by jumpers.

Important: if mechanical water meters are installed on the DHW tie-ins, then the water supply consumption will be taken into account without taking into account the water temperature, which is wrong, since you will have to overpay for hot water that was not in use.

Hot water supply can function in three ways:

From the supply pipe to the return pipe to the boiler room. Such a DHW system is effective only in the warm season when the heating system is turned off;
From supply pipe to supply pipe. Such a connection will bring maximum return in the demi-season - in autumn and spring, when the coolant temperature is low and far from the maximum;
From return pipe to return pipe. This DHW scheme is most efficient in extreme cold, when the temperature on the supply pipe rises ≥ 75 0 С.

The continuous movement of water requires a pressure drop between the start and end points of the tie-in into one circuit, and this drop is provided by flow restriction. Such a limiter is a special retaining washer - a steel pancake with a hole in the middle. Thus, the water that is transported from the inlet tie-in to the elevator encounters an obstacle in the form of a washer body, and this obstacle is adjusted by turning, which opens or closes the retaining hole.

But too much restriction of water movement in the pipeline route will disrupt the operation of the heat point, so the retaining washer must have a diameter 1 mm larger than the diameter of the heat point nozzle. This size is calculated by representatives of the heat supplier so that the temperature on the heating return pipe of the elevator unit lies within the standard limits of the temperature chart.

What is pipe filling and riser

These are pipes laid horizontally and carried through the basement of a residential building, which connect the risers with a heat point and a water meter. The bottling of cold water supply is done single, bottling hot water - in two copies.

The diameter of the DHW or cold water filling pipes can be 32-100 mm, and depends on the number of connected consumers. For any water supply scheme, ø 100 mm is too large, but this size is taken taking into account not only the actual condition of the route, but also taking into account the size of salt deposits and rust on the inner walls of metal pipes.

The pipe vertical riser distributes water to the apartments that are located above it. The standard scheme for such wiring includes several risers - for cold and hot water supply, sometimes - separately for heated towel rails. More wiring options:

Several groups of risers passing through one apartment and providing water to draw-off points located at a great distance from each other;
A group of risers in one apartment, which provides water to a neighboring apartment or several apartments;
When organizing hot water supply with pipe jumpers, you can combine up to seven groups of risers by apartments. Jumpers are equipped with Mayevsky cranes. This is called a circulating pipeline, or CHP.

The standard diameter of pipes for cold and hot water supply for risers is 25-40 mm. Risers for heated towel rails and idle risers are mounted from pipes ø 20 mm. Such risers provide both single-pipe and two-pipe heating systems at home.

Closed hot water system

The constant circulation of water in a closed hot water supply system is based on the principle of taking cold water from the pipeline and supplying it to the heat exchanger. After heating, the water is supplied to the distribution system around the apartment. The working fluid in the heating system and hot water for the technical needs of consumers are separated, since the coolant may have toxic inclusions to improve its heat transfer qualities. In addition, hot water pipes rust faster. Such a scheme is called closed due to the fact that the consumer uses heat, and not the coolant itself.

Pipe connection

The main function of the piping is to distribute water to the points of water intake in the apartment. The standard diameter of the supply pipes is 15 mm, the pipe grade is DN15, the material is steel. For PVC or metal-plastic pipes, the diameter must be the same. When repairing or replacing the piping, it is not recommended to use a smaller diameter so as not to change the design pressure parameters that the hot or cold water circulation system must comply with.

To organize the correct eyeliner, tees are most often used, with a more complex wiring diagram - collectors. Collector piping requires concealed installation, so the collector should be installed when servicing a large number of rooms in the house. After 10-15 years, metal pipes are overgrown from the inside with salt mineral deposits and rust, therefore, preventive work to restore the system's performance consists in cleaning the pipes with steel wire, or replacing old pipes with new ones.

With the seeming functionality and durability of PVC or metal-plastic pipes, it is recommended to use steel products for piping - they hold water hammer and temperature changes well. Such deviations in the DHW operating mode can often be observed when the heating system is turned on or turned off in an emergency. It is necessary to lay the pipe material in the plan of the water supply scheme of a residential building even at the stage of drawing up a project and estimate.

Galvanized metal pipes - they have been used for many decades, and they have proven themselves from the best side. The zinc layer on the metal does not allow corrosion to develop, salt deposits are not retained on it. When purchasing galvanized products, it should be remembered that welding work on such a surface is not carried out, since the weld will remain unprotected by zinc - all connections must be made on the thread;
Pipe connections on fittings for soldering copper joints last much longer than steel and even galvanized pipes. Such connections with a solder connection do not need to be serviced, and they can be laid in both open and hidden ways;
Corrugated pipe eyeliner for cold or hot water supply from stainless steel. Such products are simply and quickly mounted on threaded connections or compression fittings. No special equipment other than two adjustable wrenches is required for this. The guaranteed service life of stainless steel is not limited by the manufacturer. The only thing that will have to be changed over time is silicone seals.

Features of hot water supply and calculation of the volume of hot water

The calculation of the amount of hot water in the system depends on technical and operational factors:

Estimated hot water temperature;
The number of residents in an apartment building;
Parameters that plumbing fixtures can withstand, and the frequency of their work in the general water supply scheme;
the number of plumbing fixtures that are connected to the hot water supply.

Calculation example:

A family of four uses a 140 l bath. The bath is filled in 10 minutes, the bathroom has a shower with a water consumption of 30 liters.
Within 10 minutes, the device for heating water should heat it up to the design temperature in the amount of 170 liters.

These theoretical calculations work assuming average water consumption by residents.

Breakdowns in the hot or cold water distribution system

With your own hands, you can fix the following emergencies:

Leaking valve or faucet. This happens most often due to wear of the oil seal or seal. To eliminate the malfunction, it is necessary to open the valve completely and with force so that the raised stuffing box closes the leak. This technique will help for a while, in the future the valve must be sorted out and worn parts replaced.

Noise and vibration of a valve or tap when opening in a hot water supply system (less often - cold). The cause of noise is most often wear, deformation or crushing of the gasket in the crane box of the mechanism. Noises appear if the valve does not open completely. This malfunction can cause a series of water hammers in the pipes, so its elimination is of paramount importance. In a few milliseconds, the crane box valve is able to close the valve seat in the valve or valve body, if it is not a ball valve, but a screw one. Why is the risk of water hammer higher in DHW? Because in pipes with hot water, the working pressure is greater.

How to troubleshoot:

Shut off the water at the inlet;
Unscrew the crane box of the noisy crane;
Replace the gasket, but bevel the new gasket before installing to prevent the valve from vibrating when opening at high pressure.

The towel warmer does not heat up. The cause of the breakdown may be the presence of air in the water supply system with constant circulation of the coolant. Usually, air accumulates in a pipe jumper, which is mounted between adjacent risers, after an emergency or planned drain of water. The problem is eliminated by bleeding air jams. For this you need:

Bleed air at the highest point of the system - on the top floor;
Shut off the hot water riser, which is located in the apartment (the riser is blocked in the basement of the house);
Open all hot water taps in the apartment;
After bleeding through the taps and mixers, you need to close them. And on the riser, open the shut-off valve.

Hidden faults

At the end of the heating season, the pressure difference between the pipes of the heating main may not be observed, and because of this, heated towel rails connected directly to the DHW will be cold. This is not a cause for concern - you need to bleed the air, which equalizes the pressure, and the heating will be restored.

Providing hot water to a multi-storey building is not easy, because the DHW system must have water under a certain pressure and at a certain temperature. This is the first. Second: the hot water supply of an apartment building is a long way of the water itself from the boiler house to consumers, in which there is a huge amount of various equipment, devices and appliances. In this case, the connection can be made according to two schemes: with upper or lower wiring.

Network diagrams

So, let's start with the question of how water enters our homes, I mean hot. It moves from the boiler house to the house, and is distilled by pumps installed as boiler equipment. Heated water moves through pipes called heating mains. They can be laid above or below ground. And they must be thermally insulated in order to reduce the heat loss of the coolant itself.

Ring connection diagram

The pipe is brought to apartment buildings, from where the route is branched into smaller sections that supply the coolant to each building. A pipe of smaller diameter enters the basement of the house, where it is divided into sections that deliver water to each floor, and already on the floor to each apartment. It is clear that such an amount of water cannot be consumed. That is, all the water pumped into the hot water supply cannot be consumed, especially at night. Therefore, another route is being laid, which is called the return line. Through it, water moves from the apartments to the basement, and from there to the boiler room through a separately laid pipeline. True, it should be noted that all pipes (both return and supply) are laid along the same route.

That is, it turns out that the hot water itself inside the house moves along the ring. And she is constantly on the move. In this case, the circulation of hot water in an apartment building is carried out precisely from the bottom up and back. But in order for the temperature of the liquid itself to be constant on all floors (with a slight deviation), it is necessary to create conditions under which its speed is optimal, and it does not affect the decrease in the temperature itself.

It should be noted that today separate routes for hot water supply and for heating can approach apartment buildings. Or one pipe with a certain temperature (up to + 95C) will be supplied, which in the basement of the house will be divided into heating and hot water supply.

DHW wiring diagram

By the way, look at the photo above. A heat exchanger is installed in the basement of the house according to this scheme. That is, water from the route is not used in the hot water supply system. It only heats the cold water coming from the water supply network. And the DHW system at home is a separate route, unrelated to the route from the boiler room.

The house network is circulating. And the water supply to the apartments is produced by a pump installed in it. This is by far the most modern scheme. Its positive feature is the ability to control the temperature regime of the liquid. By the way, there are strict norms for the temperature of hot water in an apartment building. That is, it should not be lower than +65C, but not higher than +75C. In this case, small deviations in one direction or another are allowed, but not more than 3C. At night, deviations can be 5C.

Why is this temperature

There are two reasons.

The higher the water temperature, the faster pathogenic bacteria die in it.
But you have to take into account the fact that the high temperature in the DHW system is burns when in contact with water or metal parts of pipes or mixers. For example, at a temperature of +65C, a burn can be obtained in 2 seconds.

Water temperature

By the way, it should be noted that the water temperature in the heating system of an apartment building can be different, it all depends on various factors. But it should not exceed + 95C for two-pipe systems, and + 105C for single-pipe systems.

Attention! According to the legislation, it is determined that if the temperature of the water in the DHW system is 10 degrees below the norm, then the payment is also reduced by 10%. If it is with a temperature of +40 or +45C, then the payment is reduced to 30%.

That is, it turns out that the water supply system of an apartment building, meaning hot water supply, is an individual approach to payment, depending on the temperature of the coolant itself. True, as practice shows, few people know about this, therefore disputes usually never arise on this issue.

Dead End Schemes

There are also so-called dead-end schemes in the DHW system. That is, water enters consumers, where it cools down if it is not used. Therefore, in such systems there is a very large overrun of the coolant. Such wiring is used either in office premises or in small houses - no more than 4 floors. Although all this is already in the past.

The best option is circulation. And the simplest thing is to enter the pipe into the basement, and from there through the apartments through the riser, which runs through all floors. Each entrance has its own stand. Reaching the top floor, the riser makes a U-turn and, past all the apartments, descends into the basement, through which it is discharged and connected to the return pipeline.

dead end scheme

Wiring in the apartment

So, consider the water supply scheme (HW) in the apartment. In principle, it is no different from cold water. And most often, hot water pipes are laid next to the cold water elements. True, there are some consumers who do not need hot water. For example, a toilet, washing machine or dishwasher. The last two themselves heat the water to the required temperature.

Wiring diagram for hot water and cold water pipes

The most important thing is that the distribution of water supply in the apartment (both hot water supply and cold water) is a certain norm for laying the pipes themselves. For example, if the pipes of two systems are laid one above the other, then the top one should be from hot water supply. If they are laid in a horizontal plane, then the right one should be from the DHW system. In this case, on one wall it may be in the depth of the strobe, and on the other, on the contrary, closer to the surface. In this case, the laying of the pipeline can be hidden (in strobes) or open, laid on the surface of walls or floors.

Conclusion on the topic

The seeming simplicity of hot water supply in apartment buildings is determined by the inhabitants by piping inside the apartments. In fact, this is a fairly large variety of different schemes in which pipes are stretched for several kilometers, starting from the boiler room and ending with a mixer in the apartment. And, as practice shows, even in old houses today the hot water supply is being reconstructed for new improved technologies that provide hot water and reduce the loss of heat itself.

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Imagine an ordinary morning in one of the high-rise buildings in the sleeping area of our beloved city: toilet, shower, shave, tea, brush your teeth, water for the cat (or in any other order) - and go to work ... Everything is automatic and without hesitation. As long as cold water flows from the cold water tap, and hot water flows from the hot water. And sometimes you open a cold one, and from there - boiling water!! 11#^*¿>.

Let's figure it out.

Cold water supply or cold water

The local pumping station supplies water to the main from the water utility network. A large supply pipe enters the house and ends with a valve, after which there is a water meter.

In short, the water meter assembly consists of two valves, a strainer and a meter.

Some have an additional check valve.

and water meter bypass.

The water meter bypass is an additional meter with valves that can feed the system if the main water meter is serviced. After the meters, water is supplied to the house main

where it is distributed along risers that lead water to apartments on floors.

What is the pressure in the system?

9 floors

Houses up to 9 floors high have bottom pouring from bottom to top. Those. from the water meter through a large pipe, water leaves through the risers to the 9th floor. If the vodokanal is in a good mood, then at the input of the lower zone there should be approximately 4 kg/cm2. Given a pressure drop of one kilogram, for every 10 meters of water column, residents on the 9th floor will receive approximately 1 kg of pressure, which is considered normal. In practice, in old houses, the input pressure is only 3.6 kg. And the inhabitants of the 9th floor are content with even less pressure than 1kg / cm2

12-20 floors

If the house is higher than 9 floors, for example 16 floors, then such a system is divided into 2 zones. Upper and lower. Where the same conditions remain for the lower zone, and for the upper zone the pressure is raised to about 6 kg. In order to raise the water to the very top into the supply line, and with it the water rises up to the 10th floor. In houses above 20 floors, the water supply can be divided into 3 zones. With such a supply scheme, the water in the system does not circulate, it stands on a backwater. In a high-rise apartment, on average, we get pressure from 1 to 4 kg. There are other values, but we will not consider them now.

Hot water supply or DHW

In some low-rise buildings, hot water is connected in the same way, it stands on a backwater without circulation, which explains the fact that when a hot water tap is opened, cold, cooled water flows for some time. If we take the same house with 16 floors, then in such a house the hot water system is arranged differently. Hot water, like cold water, is also supplied to the house through a large pipe, and after the meter it goes to the house main

which raises the water to the attic where it is distributed along the risers and descends to the very bottom into the return line. By the way, hot water meters count not only the volume of lost (consumed) water in the house. These counters also count the temperature loss (hygocalories)

The temperature is lost when water passes through apartment heated towel rails, which play the role of risers.

With this scheme, hot water always circulates. As soon as you turn on the faucet, hot water is already there. The pressure in such a system is approximately 6-7 kg. on the supply and slightly lower on the return to ensure circulation.

Due to circulation, we get pressure in the riser, in the apartment 5-6 kg. and immediately we see the difference in pressure between cold and hot water, from 2 kg. This is precisely the essence of squeezing hot water into cold water in the event of a malfunction of plumbing fixtures. If you notice that you still have more pressure on hot water than on cold water, then be sure to install a check valve at the cold inlet, and control valves can be included in the hot water inlet, which will help equalize the pressure by about one digit with cold. Pressure regulator installation example

Everyone wants to arrange their life with comfort. Without a water supply system for an apartment building, it is difficult to imagine a solution to this problem. Hot water goes a long way from the boiler house to high-rise buildings with end users. The task of providing all residents of a multi-storey building with water supply is solved in different ways, there are several options.

Hot water supply schemes

The difference between hot water and cold water is the need for heating, so the hot water supply system is characterized by greater complexity. For different options for arranging a water supply system, different rules apply, quality standards differ.

There are two ways to provide residents with hot water:

water is taken from a cold main, and heated in a local boiler room or boiler room (usually located in the basement), sometimes a separate heat exchanger or boiler is installed in each apartment for this purpose;
water supply to residential premises of MKD is carried out directly from the heating main, this method is most common, this is how houses were built in the USSR due to simpler maintenance.

The first method has an important advantage, the quality of water with such a supply meets the requirements of GOST R 51232-98 (“Drinking water”).

The supply from the heating mains is carried out using a large number of pumps. Heating is carried out at the boiler house, and the coolant should not lose its temperature as it moves to consumers. Therefore, much attention is paid to thermal insulation, which can significantly reduce inevitable losses. Pipes of heating mains are laid under and above the ground. Laying above the ground makes repairs easier, but in severe frosts the water cools faster. It is much easier to replace pipes laid above the ground.

Features of water supply schemes

The effectiveness of the MKD water supply scheme depends on the correct piping. When the water reaches the microdistrict, a branching into smaller sections follows, each building has its own route. Further, in the water supply network, there is a division by floors, and already on the floor, the pipeline branches into apartments. Smaller diameter pipes are used after each separation to maintain the correct pressure in the water supply.

There is a return line, along which movement occurs in the opposite direction with the formation of a common contour. This ensures constant circulation, the circulation movement is carried out from top to bottom and back to the basement.

Circulation becomes a factor due to which the temperature of the water supply remains almost the same on all floors.

The creation of conditions for ensuring a constant temperature is taken into account even at the stage of developing an apartment building project. Pumps are used to properly circulate the water supply. The norms of the temperature regime are observed, the water temperature ranges from 65 to 75 degrees Celsius. This standard is used for several reasons:

high water temperature leads to the death of pathogenic bacteria;
too hot water can cause burns;
temperature limits are chosen taking into account the continuous operation of the network.

In rare cases, the dead-end hot water supply scheme for MKD continues to be used, where the coolant cools down in the apartment until it is used up. Such a system leads to excessive waste of water, becomes financially unprofitable for end users and the service organization, which, due to restrictions in this case, is unable to provide services of a suitable level.

Piping in the apartment

The wiring for DHW water supply does not differ from the cold one, there are only a couple of nuances. Some consumers do not need hot water, some use their resources for heating. The washing machine and dishwasher can provide themselves with the working fluid of the desired temperature. This also applies to some other plumbing equipment, where hot water is not needed, and heating is carried out on its own.

The following pipe laying methods are used:

laying pipes for cold and hot water supply one above the other, then the top one will be used for hot water supply;
with horizontal laying, the right pipe belongs to the DHW;
open and closed methods, for which the rules described above apply.

In the event of a water spill, closed laying methods cause additional obstacles in order to change the damaged pipes. Sometimes it is required that the replacement be carried out in a short time, this again refers to the advantages of open circuits. Laying pipes in recesses or special panels is used to give the apartment an aesthetic appearance. A protruding pipeline can spoil the look of an expensive repair, in which every detail matters.

Transportation of water from the main line to end users. Old schemes have low efficiency; during repair work, the replaced water supply systems are laid using improved technologies. New methods allow not to lose the temperature of the coolant due to constant circulation. Decent water quality is ensured on any floor, problems with temperature differences are a thing of the past.