Hot and cold water supply inside the house. Centralized hot water supply systems

The rapid development of technology allows modern people to arrange their home as comfortably as possible. This requires various types of installations: utility networks, household plumbing equipment, etc.

Let's consider the basics of arranging a water supply system in an apartment building.

It is quite a difficult task to provide water to a multi-storey building, since the building includes a large number of apartments with autonomous sanitary equipment.

The water supply system is an engineering system with pipe distribution, water pressure control devices, as well as metering units and filters.

Often, residents of multi-storey buildings use a central water supply system.

Components of a central water supply system. Types of schemes

Typically, the water supply system consists of:

• Distribution channel;
• Water intake structure;
• Purification plant.

Before water is supplied to the premises, it travels a long way directly from the pumping unit to the reservoir. After the water has been completely purified and disinfected, it enters the distribution channel. The distribution channel ensures the flow of water to special installations.

Note that the water supply system is divided into 3 types:

• Collector;
• Consistent;
• Mixed.

Often, collector wiring in a house is used if the apartments have a huge amount of plumbing equipment. The collector circuit ensures stable operation of all sanitary installations and devices.

Water supply system risers

Risers - vertical arrangement of pipes in the water supply system.

They are divided into three types:

• Heating riser;
• Water supply riser;
• Sewer riser.

Maintenance of such installations is provided by representatives of organizations such as housing and communal services, housing and communal services and others that service the house.

Let's look at some legal aspects:

1. The serviceability of communications in a residential apartment building must be ensured by the management company. Therefore, the organization must replace the risers at its own expense (if we are talking about pipes that have become unusable after the expiration of their useful service life);
2. The city or district administration is obliged to replace risers in a municipal building;
3. In the event that communication systems are privatized, residents pay for repair work.

In some cases, responsible persons try to evade their responsibilities or demand money for the work done.

In this case, it is necessary to ensure that the responsible persons fulfill their direct duties. An official application must be completed and sent. If no reaction is observed, a complaint is filed with the housing department. As a rule, such actions are quite sufficient to restore justice.

Features of supplying hot water to a residential building

The hot water supply system in the house includes two types of wiring - lower and upper.

To maintain optimal temperature conditions in the pipeline, looped wiring is often used. With the help of gravitational pressure, water circulation in the ring is ensured, even in the absence of water intake.

In the riser, the water is cooled and directly enters the heating unit. At an even higher temperature, water is supplied through the pipes. In this way, a continuous process of coolant circulation is carried out.

In addition, the hot water supply system is divided according to certain criteria:

• Local;
• Centralized;
• Open thermal;
• Closed thermal.

Important! In accordance with SNiP, it is strictly forbidden to supply non-potable hot water to pipes containing technical liquid.

Description of the closed type heating system

In recent years, the use of a closed water supply scheme has become increasingly popular. A closed system is based on the use of a heating main with a completely separate, autonomous circuit into which cold water is pumped for subsequent passage through heat exchangers.

The latter absorb heat from the main water, which is heated in a thermal power plant. In addition, other heat sources are available, but the most common among them is considered to be direct heat transfer from an open-type hot water supply.

In this case, the quality of hot water supplied to the house does not depend on the condition of the pipes located in the central heating system. A closed scheme involves the use of heat exchangers and additional pumping units.

A closed type hot water supply system has undeniable advantages over an open one: quality indicators and bacteriological properties.

A closed hot water supply circuit ensures stable temperature conditions regardless of the air temperature in winter.

Modern engineers are increasingly resorting to the use of a closed-type system, since this scheme is characterized by the highest reliability indicators for consumers.

Our topic today is the hot water supply system of an apartment building: diagrams, main elements and typical problems that a homeowner may encounter. So let's get started.

DHW and heat supply diagram

The hot water supply scheme in an apartment building can be implemented in two fundamentally different ways:

1. It uses water from the cold water supply and heats it with heat from an autonomous source. This could be a boiler installed in the apartment, a gas water heater or a heat exchanger that uses coolant from a local boiler house or thermal power plant for heating;

Please note: the advantage of this scheme is higher water quality. It must comply with the requirements of GOST R 51232-98 (“Drinking water”). In addition, hot water supply parameters (temperature and pressure) extremely rarely deviate from nominal values; in particular, the DHW pressure is always equal to the cold water pressure, taking into account the pressure loss during water withdrawal.

1. It supplies water to the consumer directly from the heating main. This is exactly what is implemented in the vast majority of residential and administrative buildings of Soviet construction, constituting 90% of the housing stock in the vast expanses of our great and vast land. In the future we will focus our attention on it.

Dear reader can find additional information in the video in this article.

Elements

So, what elements does the water supply scheme of an apartment building include?

Water metering unit

He is responsible for supplying cold water to the house.

The water meter performs several functions:

• Provides accounting of water consumption (as its name clearly suggests);
• Allows you to turn off cold water to the entire house to repair shut-off valves or eliminate spillage leaks;
• Provides rough filtration of water at the entrance to the house. For this purpose, the water meter is equipped with a mud trap.

The water meter includes:

1. Inlet and house shut-off valves (valves or ball valves located on the input side of the cold water supply system and the in-house water supply system);
2. Water meter (usually mechanical);
3. Mud tank (a tank with a drain valve, in which, due to the slow movement of water through its volume, sand, large particles of rust and other debris settle). Often, instead of a mud pan, the water metering unit is equipped with a coarse filter, in which a stainless mesh is responsible for cleaning the water from debris;
4. Pressure gauge or control valve for its installation;
5. Optionally, the water meter can be equipped with a bypass line with its own valve or ball valve on it. The bypass opens when the water meter is dismantled for repairs or verification. At other times, it is closed and sealed by a representative of the water supplier organization.

It is curious: “Vodoset”, or the organization replacing it, is responsible for the state of the cold water supply input up to the first flange of the inlet valve. The water meter is the responsibility of the organization serving the house.

Elevator unit

The elevator unit, or heating point, also combines a number of functions:

• Responsible for the operation and regulation of the heating system;
• Provides the house with hot water. Water (also the coolant of the heating system) is supplied to the in-house hot water system directly from the heating main;
• Allows, if necessary, to switch DHW between the supply and return lines of the heating main. The switch is necessary because in winter the supply temperature can reach an impressive 150°C, and the permissible maximum hot water temperature is only 75°C.

A short lecture on physics: water is heated above its boiling point without evaporating, due to excess pressure in the heating main. The higher the pressure, the higher the boiling point of liquids.

The heart of the elevator unit is a water-jet elevator, through the nozzle of which hot and higher-pressure supply water is injected into a mixing chamber filled with return water. Thanks to the operation of the elevator, a large volume of water with a relatively low temperature passes through the heating system of the house; At the same time, the water consumption from the supply is relatively small.

DHW taps are located between the inlet valves and the elevator. There can be two of these inserts (one on the supply and return) or four (two on each thread). The first scheme is typical for houses built in the 70s of the last century and older buildings, the second - for more or less modern buildings.

Why are additional inserts needed?

To answer this question, we need to jump ahead and study water supply schemes in apartment buildings.

On cold water, a dead-end scheme is always used: the water meter goes to the only bottling, which goes to the risers, which end with in-house connections. Water moves in such a water supply circuit only when drawing water.

What's going on at the hot water supply?

In houses with two hot water connections into the elevator unit, the same scheme is used.

However, it has two rather annoying drawbacks:

1. If there has been no water supply through your riser for a long time, the water has to be drained for a long time before it heats up;

Please note: if your connections have mechanical meters, they will record water consumption, ignoring its temperature. As a result, you will end up overpaying a hundred or two rubles every month for a service that you didn’t actually use.

1. Towel dryers installed on hot water supply lines, which are also responsible for heating the bathroom, will only heat up when hot water is supplied to your apartment. And, accordingly, they will remain cold most of the time. Hence the cold and dampness in bathrooms, which often become the cause of fungus.

An elevator unit with four hot water connections ensures continuous circulation of hot water through two bottlings and risers connected by jumpers.

DHW operation is possible according to one of three schemes:

1. From the supply to the return pipeline. This scheme for hot water supply to a multi-storey building is used only in the summer, when the heating is turned off: a bypass between the lines of the heating main would reduce the pressure drop at the elevator;
2. From feed to feed. This scheme is for autumn and spring with their relatively low supply temperature;
3. From return to return. So the DHW is turned on during cold weather, when the supply temperature exceeds the threshold 75 degrees.

Readers who have not forgotten the basics of physics will have a reasonable question: how is the pressure difference necessary for continuous circulation between two tie-ins in one thread ensured?

Remember: water continuously moves through the pipes between the inlet valves and the elevator. To create a pressure difference, you only need to limit the flow by placing an obstacle between the taps. This role is played by a retaining washer - a metal pancake with a hole in it.

Captain Obviousness suggests: a significant restriction in the permeability of any pipeline would interfere with the operation of the elevator unit, therefore the diameter of the retaining washers is a millimeter larger than the diameter of the elevator nozzle. This, in turn, is calculated by the organization (heat supplier) in such a way that the return temperature at the outlet from the heating point corresponds to the temperature schedule.

Bottlings

Water supply bottlings are horizontal pipes running through the basement or subfloor of a house, connecting the risers with the elevator and water meter units. There is always one cold water dispensing, two domestic hot water dispensings in the hot water circulation system.

The bottling diameter, depending on its material and the number of water consumers, varies from 32 to 100 millimeters. The last meaning is clearly redundant; however, the water supply project for an apartment building had to take into account not only the current condition of the pipelines, but also their inevitable overgrowth with sediment and rust. After 20-25 years of operation, the pipe clearance in cold water decreases by 2-3 times.

Risers

Each riser is responsible for the vertical distribution of water in apartments located one above the other.

The most typical scheme is one group of risers (hot water supply and hot water supply, optional heated towel rails) per apartment; however, other options are possible:

• Two groups of risers can pass through the apartment, supplying water to the bathroom and kitchen located at a large distance;
• Risers in one apartment can supply water not only to its residents, but also to neighbors behind the wall;
• For hot water supply, circulation jumpers can connect up to 7 risers from several apartments.

The typical diameter of cold water and hot water risers is 25-40 mm. The diameter of the risers of heated towel rails and single (without plumbing fixtures) circulation risers is usually smaller: they are mounted with a DN20 pipe.

In the hot water circulation circuit, the jumpers between the risers can be located in the apartment on the top floor or placed in the attic. The jumpers are equipped with air vents (Maevsky valves or conventional valves), which allow the air that is obstructing circulation to be released.

Eyeliners

Their function is to distribute water to plumbing fixtures inside the apartment. What is useful to know about water supply connections?

• Their typical size (for steel water and gas pipes) is DN15 (which approximately corresponds to an internal diameter of 15 mm). When replacing hoses with your own hands, it is advisable not to reduce their internal diameter - this will lead to a drop in pressure on all plumbing fixtures when water is drawn from one of them;

• Since Soviet times, apartments have traditionally used simple and cheap serial (tee) wiring. A more material-intensive collector requires, among other things, hidden installation of connections, which greatly complicates their further maintenance;

• Over time, the throughput of steel connections drops noticeably, due to the notorious overgrowing of deposits. In such cases, the pipes are cleaned with a thin steel string or, simply, replaced with new ones.

If you decide to replace the liners, we strongly advise you to opt for metal pipes. The instruction is associated with a fairly high probability of water hammer and deviations from the standard temperature in the hot water system: for example, if a forgetful mechanic does not switch the water supply from supply to return during the first frost, the water temperature can significantly exceed the maximum for any polymer pipes of 90-95 degrees.

Which pipes can be used for water supply:

Image	Description
	have been used for water distribution since Stalin times. Unlike black steel, galvanized steel is resistant to deposits and rust. An important point: galvanizing is installed only on threaded connections, since during welding the zinc in the weld area completely evaporates.
	have long proven their reliability and durability: the oldest operating copper water pipes are more than a century old, and they are in excellent condition. Soldered connections of copper pipes are maintenance-free and can be mounted hidden, in a screed or grooves.
	Corrugated stainless steel pipes compare favorably with competitors due to their extremely simple installation. To connect them, compression fittings are used, the assembly of which requires only two adjustable wrenches. The service life of the pipes themselves is characterized by manufacturers as unlimited; however, after 30 years, you, or more likely your children, will need to replace the silicone O-rings in the fittings.

Malfunctions

What problems in the operation of the water supply system can the apartment owner eliminate on his own? Here are some of the most typical situations.

Valves leaking

Description: leakage along the stem of screw valves.

• Reason: partial wear of the oil seal or wear of the rubber O-ring.
• Solution: open the valve knob all the way. In this case, the thread on the rod will tighten the seal from below, and the leak will stop.

Crane noise

Description: when you open a hot or (less often) cold water tap, you hear a loud noise and feel the vibration of the mixer. Alternatively, your neighbors faucet could be the source of the noise.

Cause: a deformed and crushed gasket on the screw valve in the half-open position causes a continuous series of water hammers. Its valve closes the seat in the mixer body at intervals of a fraction of a second. In hot water, the pressure is usually noticeably higher, so the effect is more pronounced.

Solution:

1. Shut off the water to the apartment;
2. Turn out the problematic valve housing;
3. Replace the gasket with a new one;
4. Use scissors to remove the chamfer from the new gasket. The removed chamfer will prevent the valve from beating in a turbulent stream of water in the future.

By the way: ceramic faucets are fully compatible with screw threaded faucets, and do not have the described problem.

Cold heated towel rail

• Description: The heated towel rail in your bathroom has cooled down and is not heating up.
• Cause: if the water supply scheme of a residential apartment building uses continuous circulation of hot water, the air remaining in the jumper between the risers after water is discharged (for example, for inspection and repair of shut-off valves) is to blame.
• Solution: go up to the top floor and ask your neighbors to bleed the air from the jumper between the DHW risers and heated towel rails.

If for some reason this cannot be done, the problem can be solved from the basement:

1. Shut off the DHW riser passing through your apartment, to which your connections are connected;
2. Go up to the apartment and open the hot water taps all the way;
3. After all the air has come out of the riser through them, close the taps and open the tap on the riser.

A caveat: immediately after the end of the heating season, there may be no pressure difference between the threads of the heating main. In this case, the heated towel rails will be cold even if there are no air pockets in the risers.

Conclusion

We hope that our material helped you study the water supply of an apartment building: the water supply scheme described by us is the most common. Good luck!

The pipeline for hot centralized water supply cannot be made according to the cold water supply scheme. These pipelines are dead-end, that is, they end at the last water withdrawal point. If you make a hot water supply in an apartment building using the same scheme, then the water will cool down in the pipeline at night, when it is used little. In addition, there may be such a situation, for example, the residents of a five-story building located on the same riser went to work during the day, the water in the riser was cooling down, and suddenly one of the residents on the fifth floor needed hot water. After turning on the tap, you will first have to drain all the cold water from the riser, wait for warm, and then hot water - this is an excessively high consumption. Therefore, hot water supply pipelines are made in a loop: water is heated in a boiler room, heating unit or boiler room and supplied through the supply pipeline to consumers and returned back to the boiler room through another pipeline, which in this case is called circulation.

In a centralized hot water supply system, pipelines in the house are laid with two-pipe and single-pipe risers (Fig. 111).

Rice. 111.Distribution diagrams for hot water supply in centralized systems

A two-pipe hot water supply system consists of two risers, one of which supplies water, the other drains it. Heating devices - heated towel rails - are placed on the outlet circulation riser. The water was still heated and served to consumers, but whether they will use it or not and at what time is unknown, so why waste it, let this water warm the heated towel rails and the air in damp, by definition, bathrooms. In addition, heated towel rails serve as a U-shaped compensator for thermal expansion of pipes.

A single-pipe hot water supply system differs from a two-pipe system in that all circulation risers (within one section of the house) were combined into one and this riser was called “idle” (it has no consumers). For better water distribution to individual points of water consumption, as well as in order to maintain the same diameters along the entire height of the building in single-pipe hot water supply systems, the risers are looped. With a ring scheme, for buildings up to 5 floors high inclusive, the diameters of the risers are 25 mm, and for buildings from 6 floors and above - 32 mm in diameter. Heated towel rails in single-pipe installations are placed on supply risers, which means that when the water in boiler rooms is weakly heated, it can reach distant consumers cold. Hot water will not only be supplied to nearby consumers, but it will also cool in their heated towel rails. To ensure that the water does not cool down and reaches hot water to distant consumers, a bypass is installed in the heated towel rails.

Two- and one-pipe hot water supply systems can be made without heated towel rails, but then these devices must be connected to the heating system. At the same time, in the summer, heated towel rails will not work, and in the winter, the total costs for hot water supply and heating will increase.

To ensure air removal from the system, pipes are laid with a slope of at least 0.002 to the pipeline entrance. In systems with bottom wiring, air is removed through the top tap. With overhead wiring, air is removed through automatic air vents installed at the highest points of the systems.

A constant supply of hot water to a multi-apartment high-rise building can be carried out using two methods using different operating principles:

1. In the first case, the hot water supply of an apartment building takes water from the cold water supply (cold water supply) pipeline, then the water is heated by an autonomous heat generator: an apartment boiler, a gas water heater or boiler, a heat exchanger that uses the heat of a local firehouse or thermal power plant;
2. 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 a residential building.

Important: the advantage of the second option of a water supply system for a residential building is better 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 the cold water supply, and the temperature is stabilized in the common heat generator.

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

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

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

1. It takes into account the consumption of cold water supply, that is, it acts as a water meter;
2. It can shut off the supply of cold water to the house in emergency situations or when it is necessary to repair components and parts, as well as to eliminate leaks;
3. Serves as a filter for coarse water purification: any hot water supply scheme for an apartment building should contain such a mud filter.

The device itself consists of the following components:

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

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

1. Ensures full and continuous operation of the heating system in an apartment building, and also regulates its parameters;
2. It delivers hot water to the house, that is, it provides hot water supply (hot water supply). The coolant itself in the heating system enters the hot water supply system of the apartment building directly from the centralized heating main;
3. The heating point can switch the hot water supply between return and supply. This may be necessary during severe frosts, since at this time the temperature of the coolant on the supply pipe can rise to 130-150 0 C, and this despite the fact that the standard supply temperature should not exceed 750 C.

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

Adapters for connecting DHW can be inserted between the valves at the inlet of the route and the heating station - this is the most common connection scheme. The number of inserts is two or four (one or two each on the supply and return). Two inserts are typical for old houses; in new buildings, four adapters are practiced.

On the cold water supply 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 pipes are routed to apartments. Water will move in such a cold water supply system only during disassembly, that is, when opening any mixers, taps, valves or valves.

Disadvantages of this connection:

1. If there is no water supply to a particular riser for a long time, the water will remain cold for a long time when drained;
2. Heated towel rails embedded in the DHW inlets from the boiler rooms, which simultaneously heat the bathroom or toilet, will only be hot when the DHW is drawn from a specific riser in the apartment. That is, they will almost always be cold, which will cause the appearance of moisture on the walls, mold or fungal diseases of the building materials of the room.

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

Important: if mechanical water meters are installed on the hot water taps, then the water supply consumption will be taken into account without taking into account the water temperature, which is incorrect, since you will have to overpay for hot water that was not used.

Hot water supply can operate in three ways:

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

For continuous movement of water, a pressure difference is required between the starting and ending points of insertion into one circuit, and this difference is ensured by limiting the flow. This limiter is a special retaining washer - a steel pancake with a hole in the middle. Thus, the water that is transported from the inlet to the elevator encounters an obstacle in the form of a washer body, and this obstacle is regulated by a rotation that opens or closes the retaining hole.

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

What is pipe filling and riser

These are pipes laid horizontally and carried through the basement of a residential building, which connect the risers to the heating station and water meter. Bottling of cold water supply is done in single copies, bottling of hot water supply is done in duplicate.

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.

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

1. Several groups of risers passing through one apartment and providing water to water points located at a great distance from each other;
2. A group of risers in one apartment that supplies water to a neighboring apartment or several apartments;
3. When organizing hot water supply, pipe jumpers can be used to connect up to seven groups of risers across apartments. The lintels are equipped with Mayevsky taps. This is called a circulation pipeline, or CTP.

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

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 throughout 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 because the consumer uses the heat, and not the coolant itself.

Pipe liner

The main function of the connections is to distribute water to the water collection points in the apartment. The standard diameter of the supply pipes is 15 mm, the grade of pipes is DU15, the material is steel. For PVC or metal-plastic pipes, the diameter should be the same. When repairing or replacing the liner, it is not recommended to use a smaller diameter so as not to change the design pressure parameters that the hot or cold water supply circulation system must comply with.

To organize the correct wiring, tees are most often used; for more complex wiring schemes, manifolds are used. The collector supply requires hidden installation, so the collector should be installed when servicing a large number of rooms in the house. After 10-15 years, metal pipes become overgrown from the inside with salt mineral deposits and rust, so preventive work to restore the system’s functionality consists of cleaning the pipes with steel wire, or replacing old pipes with new ones.

Given the apparent functionality and durability of PVC or metal-plastic pipes, it is recommended to use steel products for liners - they withstand water shocks 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. Pipe material should be included in the plan for the water supply scheme of a residential building at the stage of drawing up the project and estimate.

1. Galvanized metal pipes - they have been used for many decades, and they have proven themselves to be the best. The zinc layer on the metal prevents corrosion from developing and does not retain salt deposits. When purchasing galvanized products, you should remember that welding work is not carried out on such a surface, since the weld seam will remain unprotected by zinc - all connections must be made on threads;
2. Pipe connections on fittings for soldering copper connections last much longer than steel and even galvanized pipes. Such connections with a solder connection do not need to be maintained, and they can be laid in both open and hidden ways;
3. Corrugated pipe line for cold or hot water supply made of 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 the silicone seals.

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

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

1. Estimated hot water temperature;
2. Number of residents in an apartment building;
3. The parameters that plumbing fixtures can withstand and the frequency of their operation in the overall water supply scheme;
4. the number of plumbing fixtures that are connected to the hot water supply.

Calculation example:

1. A family of four uses a 140 liter bathtub. The bathtub fills in 10 minutes, the bathroom has a shower with a water consumption of 30 liters.
2. Within 10 minutes, the water heating device must heat it to the design temperature of 170 liters.

These theoretical calculations work based on average water consumption by residents.

Breakdowns in the hot or cold water distribution system

You can fix the following emergency situations with your own hands:

The valve or faucet is leaking. 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 oil seal stops the leak. This technique will help for a while; in the future, the valve must be rebuilt and worn parts replaced.

Noise and vibration of a valve or faucet 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 gearbox of the mechanism. Noises appear if the tap is not opened all the way. This fault can cause a series of water hammers in the pipes, so its elimination is of utmost importance. The faucet valve is capable of closing the valve seat in the faucet or valve body in a few milliseconds, if it is not a ball valve, but a screw valve. Why is the risk of water hammer higher in hot water supply systems? Because in hot water pipes the operating pressure is higher.

How to fix the problem:

1. Shut off the water at the inlet;
2. Unscrew the valve housing of the noisy faucet;
3. Replace the gasket, but before installing, chamfer the new gasket so that the valve does not vibrate when opening under high pressure.

The heated towel rail does not heat up. The cause of the breakdown may be the presence of air in the water supply system with constant coolant circulation. Typically, air accumulates in a pipe jumper, which is installed between adjacent risers, after an emergency or scheduled drain of water. The problem is eliminated by bleeding the air plugs. To do this you need:

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

Hidden faults

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