Description:

The design of hot water supply networks is often carried out empirically or very approximately. Meanwhile, the importance of networks requires a completely different, deeper approach, in which there is no place for improvisation and chance.

Hot water supply. Network calculation

The design of hot water supply networks is often carried out empirically or very approximately. Meanwhile, the importance of networks requires a completely different, deeper approach, in which there is no place for improvisation and chance.

One of the problems that requires special attention when designing a hot water supply network is user discomfort caused by a certain waiting period from the moment the water-folding device (mixer, tap) is opened until the moment when really hot water flows from it. Supply network hot water(Fig. 1) in the absence of water intake is filled cold water, not hot. When you open the water tap from a tank or instantaneous water heater, hot water begins to flow into the pipeline, but hot water will flow from the water tap only after some time, when all the cold water has poured out of the supply pipeline. In such a network, a long period of time between the opening of the water tap and the arrival of hot water is quite acceptable for single-family residential buildings and completely unacceptable for large distribution networks, such as hotels or other public facilities.

Pros and cons of circulation networks

The most obvious solution is to install a permanent circulation network (Fig. 2). Such a network provides almost instantaneous supply of hot water and, of course, is optimal, radically solving the above problem. Its disadvantage is its high cost, due to which the network is justified only with a significant number of users. In addition, the constant circulation of hot water leads to heat loss, and this is a significant addition to the overall energy bill. Therefore, on medium-length networks, it is advisable to first carefully study location of water taps to reduce the length of supply pipelines and understand whether it is advisable to use a system without circulation with an acceptable waiting period for hot water supply.

In Italy there is no corresponding regulation for the waiting period. A period of up to 60 seconds is considered quite acceptable, but only in housing construction. For other higher status properties, the acceptable waiting period has been reduced to 30 seconds.

Justification of the hot water supply scheme (calculation of the waiting period)

To optimize the waiting period, the time required for hot water to arrive is calculated.

water into the water supply device furthest from the storage tank or heat generator. If the result exceeds generally accepted indicators, the task is to modify the network so that the waiting period falls within the established limits. In this regard, it should be taken into account that the waiting period:

– the shorter, the higher the pressure of the water coming to the point of water collection;

– the shorter, the more throughput water folding device;

– the longer, the larger the volumes of the sections forming the most distant circuit, as well as the larger the cross-section of the pipeline.

The calculation is made in the following order:

1. Determine the peak (maximum) consumption of hot water for water collection (see below), then the length, type and diameter of each section of the supply pipeline;

2. Multiply the total length, m, of the pipeline of each diameter by the specific volume of water, l/m (Table 1);

3. Determine the calculated path for the least advantageously located water tap (furthest from the water heating equipment) and sum up the volumes of water in the pipeline sections to the water tap.

4. Calculate the time of actual receipt of hot water, for which they divide the sum of the volumes of water in the pipelines along the calculated path by the second flow rate of the water tap at the design pressure in front of it (the second flow rate of the water tap is usually indicated by the manufacturer).

The most labor-intensive calculation is the calculation of the specific volumes of pipelines Cs. The following formula is used for this:

Cs = 10 (F /100) 2 3.14/4

where F is the internal diameter of the pipeline (not external or nominal), mm.

To simplify the calculations in the table. 1 shows the specific volumes of water in steel, CPVC, copper pipelines for the most common pipe diameters used in hot water supply networks.

The cost of such a network is lower, but on long-distance networks the waiting time for hot water to arrive at a remote water tap is too long.

In almost all cases, this solution ensures a rapid supply of hot water from the water tap, but has higher construction (purchase) and operational costs. Constant circulation of hot water leads to significant heat loss and is technically less reliable due to the presence of a pumping unit.

Calculation example

As an example, consider a hot water supply network similar to that shown in Fig. 1. The most remote water tap has a calculated second flow rate (throughput capacity) of 0.15 l/s and is connected to the primary source of hot water (water heating equipment) in three sections: the first (A) – a copper pipeline with a diameter of 3/4”, length 8 m, the second (B) is copper 1/2” 18 m long and the last (C) is copper 3/8” 1 m long.

Calculation of water volumes in pipelines in accordance with the recommendations of table. 1:

A) volume of water in a 3/4” section: 8 m x 0.314 l/m = 2.512 l

B) volume of water in a 1/2” area: 18 m x 0.122 l/m = 2.196 l

B) volume of water in a 3/8” area: 1 m x 0.086 l/m = 0.086 l

The total volume of water in the pipelines will be

(2.512 + 2.196 + 0.086) = 4.794 l.

Time for hot water to arrive at the tap: (4.794 l / 0.15 l/s) = approximately 32 s.

In a water supply network with a collector distribution (Fig. 3), to which distribution pipelines are connected to water taps, and connected directly to equipment for heating and supplying hot water, the most remote point from those connected to the collector is the point of the pipeline 3/8” long ( 8 + 18 + 1) = 27 m. The volume of water in the circuit is reduced to (27 x 0.086) = 2.332 l. The waiting time for hot water to arrive at the farthest water tap is reduced to 2.332 / 0.15 = approximately 15.5 s, which can be considered an absolutely acceptable indicator.

Calculation of daily hot water consumption

Determining the volumes of hot water and heat consumption required for engineering calculations of capacitive and high-speed water heaters is possible only if there is reliable data on the social purpose of the facility in which the hot water supply is being designed. In other words, it would be wrong to take as a basis for our country the parameters of Northern European countries or, worse, America, where the lifestyle is decidedly different from ours, as a result of which hot water consumption has little or nothing in common with the Italian model.

As an illustration in table. Table 2 shows the consumption of hot water in the residential sector, as well as in trade and service enterprises.

Pipeline calculation

Firstly (and this is the main thing), the hot water supply pipeline must be calculated for peak (maximum) periods of water withdrawal based on the tables and diagrams used to calculate heating pipelines.

Materials used (in order of popularity): galvanized steel, copper and CPVC.

According to the pipeline calculation method from the ASHRAE Association's practical guide (ASHRAE Handbook 2003 Application), for each type of water tap, a conditional element is assigned - an equivalent FU (Fixture Unit) device.

The calculation is performed using the following method:

1. The FU equivalent is determined at each water intake point according to the table. 3;

2. The supply (distribution) network is divided into sections according to the same principle as heating circuit networks;

3. The sum of equivalent FU devices served by each section of the pipeline is determined;

5. The diameter of each section is determined depending on the calculated flow rate (throughput volume) and the length of the section so that the pressure loss throughout the network as a whole does not go beyond acceptable limits.

The diameter of the circulation network (if it is decided to organize one) can be determined by taking for each calculated section of the pipeline a throughput volume of 3 l/s for each conditional element FU of the supply linear branch from which it departs. The recirculation pump must be designed for a throughput capacity equal to the sum of the FU elements of the water supply points of the entire supply network.

To prevent wasteful energy consumption inherent in any circulation network, it is recommended to equip the pump with a thermostat, which should turn on the pump when the circulation (return) water temperature drops below a certain set level and turn off the pump when the return water temperature is approximately 5 °C below the set hot water value .

Water taps are mixing devices (cold and hot water are mixed to obtain the temperature desired by the consumer at the spout) and such a device (mixer) is not always of a thermostatic type. The calculation must be performed for the supply (distribution) network of both cold and hot water supply so that at each water intake point (at the cold and hot water mixer connections) the pressure difference is minimal, firstly, and the pressure of cold and hot water is constant, in -second. These are especially important when installing a bathtub or shower stall at the end sections of the network, in which any sudden pressure drop in a cold or hot water supply leads to an arbitrary unregulated decrease or increase in the temperature of the supplied water.

Legionella Pneumophila Control

Legionella pneumophila bacterium, which has been written about extensively in the specialized literature, multiplies in stagnant areas of the hot water distribution network. But it reproduces in water whose temperature does not exceed 46 °C. It is logical to assume that the problem can be solved by heating and supplying hot water with a temperature above 60 °C to the network. In Italy, however, water temperatures exceeding 46 °C are prohibited by law. Therefore, to prevent the occurrence of Legionella outbreaks in the water supply network, periodic disinfection of the pipeline is necessary. To disinfect, very hot water or water with antibacterial additives is pumped through the pipelines for several hours.

Reprinted with abbreviations from Impianti magazine No. 27/2005

Translation from Italian by S. N. Bulekov

Technical editing by V. N. Isaev

In order for any residential building to function normally, it is necessary to install a water supply system. Its proper design will ensure timely supply and sufficient water pressure. This article will discuss in detail the hot water supply scheme, types of connection and its features in an apartment building.

What is special about the water supply of an apartment building?

It is very difficult to provide water to a building with a large number of storeys. After all, the house consists of many apartments with separate bathrooms and plumbing fixtures. In other words, water supply schemes in apartment buildings- this is a kind of complex with separate pipe distribution, pressure regulators, filters and metering equipment.

Most often, residents of high-rise buildings use water from the central water supply. With the help of a water supply, it is supplied to individual plumbing fixtures under a certain pressure. Often water is purified using chlorination.

Composition of the central water supply system

Centralized water supply schemes in multi-storey buildings consist of a distribution network, water intake structures and treatment plants. Before getting into the apartment, water travels a long way from pumping station to the pond. Only after purification and disinfection is water sent to the distribution network. With the help of the latter, water is supplied to appliances and equipment. The pipes of the central hot water supply circuit of a multi-storey building can be made of copper, metal-plastic and steel.

The latter type of material is practically not used in modern buildings.

Types of water supply schemes

There are three types of water supply system:

• collector;
• sequential;
• combined (mixed).

Recently, when in apartments there is increasingly a large number of plumbing equipment, use collector wiring diagram . She happens to be the best option normal functioning of all devices. The collector-type hot water supply scheme eliminates pressure drops at different connection points. This is the main advantage of this system.

If we consider the diagram in more detail, we can conclude that there will be no problems with using the plumbing equipment for its intended purpose at the same time. The essence of the connection is that each individual water consumer is connected to the cold and hot water supply riser collectors separately. The pipes do not have many branches, so the likelihood of leakage is very low. Such water supply schemes in multi-storey buildings are easy to maintain, but the cost of the equipment is quite high.

According to experts, the hot water supply collector circuit requires the installation of a more complex installation plumbing fixtures. However, these negative sides are not so critical, especially considering the fact that the collector circuit has many advantages, for example, hidden installation of pipes and taking into account the individual characteristics of the equipment.

Sequential hot water supply circuit multi-storey building - this is the easiest way to wire. This system is time-tested; it was put into operation during the Soviet era. The essence of its device is that the cold and hot water supply pipelines are parallel to each other. Engineers advise using this system in apartments with one bathroom and a small amount of plumbing equipment.

Popularly, such a hot water supply scheme for a multi-storey building is called a tee scheme. That is, from the main highways there are branches that are connected to each other by tees. Despite the ease of installation and savings in consumables, this scheme has several main disadvantages:

1. In the event of a leak, it is difficult to look for damaged areas.
2. Inability to supply water to a separate plumbing fixture.
3. Difficulty in accessing pipes in case of breakdown.

Hot water supply for an apartment building. Scheme

Pipe connections are divided into two types: to the hot and cold water supply riser. Briefly they are called cold water and hot water. Special attention hot water system deserves apartment building. The DHW network diagram consists of two types of wiring - lower and upper. To save high temperature Looped wires are often used in pipelines. The gravitational pressure forces the water to circulate in the ring, despite the absence of water intake. In the riser it cools and enters the heater. Water with a higher temperature is supplied to the pipes. This is how continuous circulation of the coolant occurs.

Dead-end highways are also not uncommon, but most often they can be found in utility rooms industrial facilities and in small residential buildings with low number of floors. If water selection is planned intermittently, then a circulation pipeline is used. Engineers advise using hot water supply in apartment buildings (the diagram was discussed above) with a number of floors of no more than 4. A pipeline with a dead-end riser is also found in dormitories, sanatoriums and hotels. Dead-end network pipes have a lower metal consumption and therefore cool faster.

DHW networks include a horizontal main pipeline and distribution risers. The latter provide pipe distribution to individual objects - apartments. DHW is installed as close as possible to plumbing equipment.

For buildings with a large length of main pipes, schemes with circulation and looped supply pipelines are used. A prerequisite is the installation of a pump to maintain circulation and constant water exchange.

Two-pipe DHW circuit - Photo 07

Modern builders and engineers are increasingly resorting to the use of two-pipe hot water systems. The principle of operation is that the pump takes water from the return line and supplies it to the heater. This pipeline has a higher metal consumption and is considered the most reliable for consumers.

Good afternoon I ask you to consider the heating and hot water supply scheme proposed by the architect in a one-and-a-half-story private house from Porotherma-51, 150 sq.m. in the Moscow region.

There is a suspicion that the scheme is highly redundant and significant savings could be made on equipment and further operation.

There is gas in the village, but it is quite possible that by the time you move into the house

it will not be available yet, so it is necessary to provide a backup scheme for the first period of residence until gas is connected (which will then serve as a backup in case of gas interruptions). For heating, a solid fuel boiler was assumed for this purpose (in explanatory note no about him, because there are still doubts about him

), and for hot water an electric boiler.

Explanatory note on heating:

The heat source for the building under construction is the IHP (boiler room room 2) located on the 1st floor of the building in axes B-B/3-4. The coolant in the heating circuit is water with parameters 80 - 50°C

The project provides for a 2-pipe closed dead-end heating system. The heating system of the 1st floor has 2 circuits. Circuit T1 with a length of 30 linear meters. and contour T2 with a length of 32 linear meters. The heating system of the attic floor has 1 T3 circuit with a length of 29 linear meters.

The heating devices are steel panel radiators from Kermi with bottom and side connections and a built-in thermostat. For the staircase, devices without control valves are provided.

Main pipelines, heating system risers and floor wiring are made of polypropylene pipes D.20mm and risers for the attic floor D.25mm..

For devices with bottom connections, pipelines are laid on the floors. The pipelines are insulated with foam rubber-based material 13 mm thick.

On floor heating pipelines, automatic balancing valves from Oventrop are installed.

The heat transfer of heating devices is regulated by installing individual thermostatic valves.

Air removal - through air valves in heating devices, and through automatic air vents at the highest points of the system. The system drains at the lowest points.

The project provides for the installation of water-heated floors in rooms 01; 07; 08.

Explanatory note on hot water supply:

The project provides for autonomous hot water supply to the building.

The hot water supply system is provided with forced circulation through mains and risers.

Hot water preparation is provided in the boiler room

The calculated flow rate and pressure for hot water supply needs is provided by cold water supply pumps.

Main and distribution pipelines for hot water supply are laid in floors and in grooves along the walls and in an open way along the walls, risers - in an open way along the walls.

Main pipelines and hot water supply risers are made of reinforced polypropylene pipes, diameter 25mm; wiring and connections to sanitary fixtures are made of polypropylene pipes, diameter 20mm.

Shut-off valves are provided, which are installed:

● on branches feeding storage tanks;

● on risers;

● on floor connections to bathrooms;

● on branches for preparing hot water.

Any pipeline or riser is equipped with a shut-off valve with drain device at the lowest point in order to allow partial shutdown of one of the pipelines without closing the entire distribution network.

The following Energoflex Super hot water supply pipelines are insulated against heat loss with a thickness of 13 mm:

Main pipelines;

Stoyakov;

Pipelines laid in floors and grooves.

Hot water is prepared using a gas water heater in the boiler room. Storage and distribution tanks for cold water and hot water are installed in the boiler room.

Hardware Specification:

1 pc Single-circuit gas heating boiler with a power of 27 kW 1 pc Solid fuel backup boiler 1 pc Gas water heater 1 pc Electric boiler 300 l or more (backup hot water supply) 1 pc Storage tank 300 l or more 3 pcs Steel panel radiators with bottom supply 22 type 500x500 mm 8 pcs Steel panel radiators with bottom supply Coy 22type 500x600mm 3 pcs Steel panel radiators with bottom connections 22type 500x800mm 1 pc Manifold group for radiator heating 1 pc Manifold group for “warm floors” 1 pc Safety group 30 linear meters Reinforced PP pipe PN25 D. 25mm160 linear m. Reinforced PP pipe PN25 D. 20mm200 linear m. Polyethylene pipe D. 16mm 1 piece Membrane expansion tank 30-40l1 Comp. Gas boiler chimney pipes (stainless steel) 1 Comp. Gas water heater chimney pipes (stainless steel) 6 pcs. Circulation pump (90-120Vit) 30 sq. m. Underfloor heating 1 piece Manifold cabinet 500x600mm

Our questions:

1. In our case, what is better than one double-circuit boiler or a separate boiler and water heater?

2. Is the choice of a backup system optimal (solid fuel boiler and electric boiler) or can you recommend something better?

3. How can you estimate the approximate cost of equipment and further operation for various options? (maybe you can advise on some examples of calculations)

4. Please double-check the heat calculations for the premises (presented in the attached drawings), there are doubts about its correctness.

5. Please point out other shortcomings in the project.

Additional Information:

WE DON'T WANT TO PAY EXTRA MONEY

There are frostbites in the family (comfortable temperature is at least 22 degrees)

There will be a bath on the second floor (in terms of having enough hot water for it)

It is advisable that the delay of hot water after turning on the tap should not be more than a few seconds

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 best quality water, which is regulated by GOST R 51232-98. Also, when taking hot water from a centralized heating main, the temperature and pressure of the liquid are quite stable and do not deviate from the specified parameters: pressure in the pipeline hot system water supply is maintained at the level of 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 it is this scheme that is most often used both in urban areas and in country houses, including country 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 coarse water purification filter: 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 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 standard indicator The supply temperature should not exceed 750C.

The main element of the 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 supply 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 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 - 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. Standard scheme 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 single-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 line requires hidden installation, so the collector should be installed during maintenance large quantity 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 except two adjustable wrenches, this is not required. 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. Parameters that plumbing fixtures can withstand and the frequency of their operation general scheme water supply;
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 the pipes with hot water working 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 reason for concern - you need to bleed off the air, which equalizes the pressure, and the heating will be restored.

Water supply is one of the most important systems country house or apartments. Of course, before starting the assembly of communications of this type, a detailed project with all calculations must be drawn up. This will ensure an efficient and uninterrupted supply of hot and cold water in the future.

Design of hot and cold water supply: main stages

When drawing up a water supply project, you first need to decide:

• with a water pumping source;
• the type of equipment intended for its collection;
• method of external wiring of highways;
• internal or apartment.

The source of water is usually a well. Its drilling should be the first stage in the arrangement of a water supply system for a residential building. Initially, you should decide on the diameter of the shaft. To provide water to 4-6 people living in a house, a casing pipe cross-section of 132 cm will most likely be sufficient. After completion of the drilling work, the owner of the house should be issued a well passport indicating its parameters.

Based on these data, as well as based on the needs of the people living in the house, the parameters of the equipment intended for water intake are selected. Power calculation deep well pump is based on the pressure of the supplied water and its flow rate. The pressure is determined by the formula H=Hr+S+Hcv, where Hr is the height of the external pipeline level relative to the dynamic level of the shaft, S is the total pressure loss, Hsv is the pressure required when introducing the pipe into the building.

The water supply line to the house is connected to the pump through check valve. It should be stretched along a trench buried below the freezing point of the soil.

Cold water supply design

Pipes can be installed inside a building in two ways:

1. Consistently. In this case, the lines are led through utility rooms (kitchen, bathroom) and in appropriate places, connections are made from them to plumbing fixtures.
2. Collector. With this method, the internal wiring consists of two or three circuits, each of which serves a separate group of rooms. This method of internal wiring is usually included in the design of a large cottage.

Internal piping in a water supply system can be open or closed. In the first case, a neat appearance premises. The second has easy access for maintenance.

Features of DHW design

Water is heated in the DHW system by connecting the lines to a double-circuit boiler or boiler. For a small cottage, an instantaneous water heater can also be used. When drawing up a hot water supply project, you should consider the following:

• DHW risers are located to the right of the cold water supply risers;
• DHW pipelines are laid above cold water pipelines.

The choice of shut-off valve parameters depends on such characteristics as operating pressure in the lines.

Pipe selection

When designing hot and cold water supply systems, among other things, you should decide on the type of pipes used for the installation. Plastic or metal-plastic ones are usually used indoors in apartments and houses. In small dachas, steel ones can also be installed. These are very reliable pipes. Their disadvantage is considered to be difficulty in assembly and tendency to rust. In large cottages, copper pipes are sometimes used to install water supply. This option is very expensive, but is durable. In addition, copper gives drinking water unique properties. When drawing up a copper water supply project, it is taken into account that such pipes should not come into direct contact with any aluminum parts. For the external main, HDPE (food grade plastic) pipe is usually used.

Our highly qualified specialists will design the hot and cold water supply for your home in compliance with all rules and regulations. Our advantages include, among other things, the low cost of carrying out such work. You can also order installation of a designed water supply system from us.