What is a bypass and why is it needed? Bypass: what is it and how to install it? Alternative ways to raise your temperature

The uninterrupted functioning of engineering communications of buildings is extremely important to ensure the normal functioning of people. In heating systems and plumbing, a bypass is often used - a backup pipeline that helps in various emergency situations. Our article will help you understand why a bypass is needed in a water supply system.

Why do you need a bypass?

Bypass is used as a backup path, which is required for reliable operation engineering systems in case of an emergency or for repair work.

It applies:

during the construction of oil and gas pipelines;
in systems pumping various liquids, including milk and gasoline;
in central power supply structures;
in water supply and sanitation;
in heating systems, etc.

The bypass is a parallel pipeline branch installed in key places contour. This section of a backup pipe, which has shut-off and control valves, is intended to drain the transported medium from the main pipeline and supply it into it (SNiP I-2). The main purpose of the design is to create a parallel flow of working fluid, bypassing any section of communications.

In water supply systems, as in other structures, when emergency situations arise, there is a need to direct water moving under pressure along a backup path, blocking the emergency route.

One of the tasks of a bypass in water supply systems is the ability to use a backup pipeline to remove an individual pipeline that needs verification or repair. There is no need to turn off the water. This is especially important in boiler rooms or medical institutions where a constant water supply is necessary.

On a note! Locking device on the bypass branch must be sealed in the closed state (SP 30.13330).

The bypass circuit is used in the piping scheme of the pool water treatment unit.

A bypass is also installed on filtration systems, which allows for scheduled or emergency maintenance of equipment without shutting off the water supply to the building. The bypass line can be installed both on the entire filter system and on a specific module.
You cannot do without a bypass in systems with installed pumps for supplying water cooling reactors or blast furnaces, when the pumps cannot be turned off for repairs. The emergency section is closed by turning on the pump on a parallel branch, which ensures the continuity of the production process.
In water heating systems equipped with circular pumps, failures due to power outages are not uncommon. Using a bypass, you can organize natural circulation of water by blocking its access to the pump and running it through the central heating pipe.

Using a bypass pipe, you can, if necessary, regulate the volume of hot water acting as a coolant, thereby establishing the required temperature in the room and reducing heating costs.
The bypass also allows you to replace the radiator if it breaks without turning off the heating in the house. The same role is played by the jumper installed in front - it ensures the direction of the flow of hot water bypassing it for repairs or the ability to maintain the required temperature of the coolant in the device.

Bypass types

Bypass pipelines can be made of metal-plastic, polypropylene or metal.

Bypasses differ according to their purpose and type of shut-off and control valves, on which the price of the devices depends.

Type of shut-off valves

Bypasses with check valve.

These taps operate autonomously and do not require human intervention. Such devices are especially convenient in systems with an installed circulation pump.

When there is sufficient pressure exerted by the coolant, the valve opens; if the pressure drops, it closes, blocking the access of water.

Important! In water supply and heating systems where check valves are installed, the use of coolant with impurities is not allowed. Otherwise, the valve may become deformed and fail. To avoid contamination of the device, it is recommended to install a coarse filter.

Bypasses with tap. Ball or three-way valves can be used. The bypass is controlled by mechanically opening or closing shut-off valves.

Important! Unused for a long time Ball Valves may stick, so they should be opened and closed from time to time.

Purpose

In everyday life, bypasses are mainly installed for:

the possibility of servicing individual devices without shutting down the entire water supply or heating system, when to repair or replace equipment it is enough to close the locking devices and run water through the backup pipeline;
increasing the efficiency of the heating system (single-pipe);
eliminating the dependence of the functioning of utilities on electricity.

When installing a bypass pipeline, several important nuances should be taken into account:

You can make a bypass yourself from a pipeline, or purchase a ready-made device.
It is recommended to install the bypass pipeline simultaneously with the installation of the water supply or water heating system.
The bypass diameter must be smaller than the diameter of the main pipeline.
The backup outlet should be installed as far as possible from the riser.
Depending on the material from which it is made, the bypass installation can be carried out either by welding or by means of a coupling connection.

As an example of how a bypass can be installed in a house, consider installing a jumper in front of the entrance to the heated towel rail. This device is extremely important if you need to remove the equipment itself without turning off the riser. Also, the presence of a bypass is useful if you need to reduce the pressure in the dryer pipe and maintain a certain drying mode.

Brief instructions for installing a bypass on a heated towel rail connected to a DHW pipe:

The hot water in the riser is turned off.
Pipe installation can be carried out using welding. It is more convenient to install the structure if there are threads on the pipes, tees and bypass. Otherwise, it will have to be cut. To seal joints, sealants and fibrous materials are used (material options are shown in the photo).

A jumper is installed between the inlet and outlet pipelines.

Where it connects to the heated towel rail, taps are installed (or a ready-made bypass with installed valves is used).

A heated towel rail is mounted on the wall.
It connects to the valves.

Equipment with an outlet that allows the heated towel rail to function more fully has been installed.

The video in this article may be helpful.

Connecting a heated towel rail with a bypass cannot be classified as a complex technological operation, but rules must be followed so as not to negate the efforts expended.

Bypass in water supply is used mainly to bypass any important components, which allows for equipment maintenance without shutting off the water supply. This is a rather important device, the use of which should not be neglected.

Bypass is a side pipe or bypass that serves for the normal operation of the coolant, bypassing heating devices installed in an isolated apartment. One end is connected to the hot water outlet, the other to the coolant input. The bypass allows you to replace radiators in rooms during the heating season, carry out maintenance of heating devices and more. Very often the bypass tap is sacred, which causes controversial debates. Whether this can be done or not, we’ll figure it out in the article.

There are three types of bypasses:

Unregulated - simple pipe;
With manual control – valve with divisions;
Automatic – with sensors;

The latter option is installed in a harness with a pump. Typically, automation is used when circulating a coolant along a circuit. An electrically powered pump allows you to increase the flow rate, which helps reduce heat loss. Most often, such a system is used in private homes or when connecting a heated floor to a heating system in apartment buildings. In the event of a power outage, the coolant flow passes through the bypass. The impeller restricts the flow of water. It is supplied to the market in two variations: injection and valve. The biggest disadvantage of an automatic bypass: if the water contains scale, scale, rust and other contaminants, it quickly fails. The bypass must be installed in a single-pipe system; if it is necessary to make a collector wiring, the jumper allows you to divide the flows into two parts, providing both radiators with coolant in equal proportions. With horizontal wiring, the bypass is installed parallel to the main line below the normal wiring. When installing standard three-quarter inch pipes, it is recommended to install a bypass at one-half inch. In this case, the pipes of the incoming and outgoing coolant flow should have a diameter of 1 inch.

Connection diagram

The standard bypass connection diagram in an apartment is as follows:

Pipe with incoming coolant flow;
Bypass;
Pipe with outgoing coolant flow;
Shut-off valves for inlet and outlet.

In that brief description we will consider with bypass. Two valves are mounted at the inlet and outlet of the radiator. The coolant is supplied from below or from above. For most heating systems, the second option is correct. When hot water is supplied from above, the liquid reaches the bypass and is divided into two streams. The coolant is directed to sections of the heating device, heating it. The other flow through the outlet pipe - the bypass, bypassing the radiator, goes down, and then continues its movement along the riser. A valve installed at the radiator inlet allows you to control the flow, increasing or decreasing the coolant supply. Installed on the bottom of the radiator shut-off valve allowing heat to be removed. During the heating season, the drain valve is opened all the way.

Why install a bypass

More hot water passes through an additional tube connecting the incoming and outgoing flows, and correspondingly less of it enters the radiator. This is normal and fully complies with housing and operational standards, if good circulation of hot water is ensured and the standards for heating the room are observed. In practice, in apartment buildings on the upper and lower floors (depending on the type of coolant supply), there is a significant decrease in temperature in the radiators due to the natural cooling of the coolant. In this case, additional losses through the bypass affect the rate of heating of the room. Delivered to the apartment from common system Hot water usually does not circulate well due to accumulated rust and scale. In some cases, pipes are installed incorrectly, with a narrowed inlet flow diameter.

What problems does a bypass valve solve?

Considering the cost of the work, it makes no sense to dismantle the bypass. Installing an additional valve will help solve the problem of reduced thermal conductivity. After closing the tap on the bypass pipe, all the coolant enters the radiator, resulting in the maximum amount of heat passing through the heating device. If it gets warmer outside or the water temperature in the radiator is too high, the bypass tap can be opened again, and then the apartment will become a little cooler.

Valve design

A standard three-quarter-inch valve is designed to provide acceptable pressure and coolant flow rate for one radiator. If you take a standard size pipe and compare it with the diameter of the valve, you can see a significant narrowing in the diameter of the latter. A valve with a smaller diameter is installed to increase pressure. The narrowed hole interferes with the normal circulation of the coolant, thereby disrupting the heat supply to one or more risers. A slight narrowing of the diameter will cause the room temperature of all neighbors to drop. In addition, in the neighboring rooms of the apartment, the batteries will begin to cool faster.

About responsibility for installing a bypass valve

Having received a dozen complaints, representatives of the housing maintenance service will come with an inspection and quickly discover the problem. The apartment owner will be required to correct problems in the system at his own expense. It is quite possible that the blame for the low temperature in the batteries lies with the housing office itself or the company providing technical repair. But all accusations will be directed towards the person who installed the tap on the bypass, disturbing the thermal balance. If several people install such taps, this will lead to a heating collapse. The whole house can be damaged. The design of some multi-storey buildings assumes the following: the coolant can rise in one riser, pass along the technical floor, and fall in another, thus continuously circulating. By placing a barrier at one point in the system, the tenant disrupts the thermal balance in two risers at once. Another riser may well be located in the same apartment. The result will be the following situation: one battery, located in the living room, heats better, the other, located in the next room or kitchen, heats worse.

Conclusion

Alternative ways to raise your temperature

The surest solution is to increase the number of radiator sections. The longer the heating device, the more heat it can release into the room. Second method: replace the fans installed at the inlet of the heat flow battery with standard ball valves. Ball valves allow water to pass through the entire ceiling without restriction. Unfortunately, using such a faucet you cannot adjust the coolant flow. A plus is good water circulation in all directions. Another disadvantage of ball valves is the effect of sticking of internal parts. After a long period of inactivity, the faucet stops turning off the flow of water. Ball valves require periodic maintenance. They must be opened and closed periodically.

How to solve the problem without a bypass valve

To prevent the bypass from taking away precious heat, you need to install an adapter pipe with a diameter smaller than the inlet and outlet pipes. Liquid always follows the path of least resistance; the lower the pipe diameter, the greater the pressure and vice versa. The water entering the apartment is immediately divided into two streams, the first goes down, the second passes through the battery. Therefore, the rules for using heating appliances recommend setting the diameter of the jumper one unit less than that of the direct-flow pipe. For example, if the pipe diameter is 1 inch, a three-quarter jumper must be installed. This will get rid of the effect of the first sections of the radiator being too hot and the last sections being quite cold. Since the liquid moves into the drainage system with some resistance, the pressure at the entrance to the batteries increases, and all sections receive an equal amount of heat. Narrowed bypasses are provided for by the standards; the local HOA or housing cooperative will have no complaints.

What to do if the bypass valve is already installed

In this case, there are only two options: keep it open all the time, in which case it makes no difference whether it is installed or not; Replace the outgoing and incoming valves with ball valves.

Is it possible to dismantle the bypass?

It is not recommended to remove the jumper between the two pipes. In the standards for the construction of residential premises, back in the seventies, it was decided to install such jumpers for central heating radiators. The bypass helps ensure the smooth flow of coolant through your apartment, regardless of whether heat enters the radiator or not. Why this is necessary: Without sealing the battery, there is no way to prevent leakage. If the heating device becomes clogged, you will have to turn off the system and leave an entire riser or two without coolant.

The bypass is an important part in the heating system, which is important for accurately regulating the flow of coolant to the radiators. In this case, the pumping equipment is mounted on a separate pipeline. Before installation, you need to find out what a bypass is in a heating system. This simple device performs the same functions as a radiator piping and can optimize the operation of the entire heating circuit.

This product allows you to optimize the functioning of the structure

A bypass is a jumper that includes a section of pipe that is mounted in certain places in the piping. To learn more about what a bypass is in heating, it is worth considering that this structural element is more often in demand in single-pipe schemes. In them, the coolant is moved from one heating device to another, followed by the return of the cooled liquid to the collector.

The mechanism is mounted on a radiator between the input and output. This device passes part of the liquid through itself to regulate the flow rate on a specific device. In this case, there is no need to completely disable the structure.

Bypass installation provides the following positive aspects:

Such equipment must have certain certificates. Before purchasing, you should inspect the product for corrosion, dents or chips. The threads should tighten well and unscrew easily.

Helpful advice! The faucet of the device must be especially reliable. It can be rod or ball.

Heating radiator piping with bypass

Having decided why a bypass is needed in the heating system, you can begin installation work. At the same time, calculations are made and components are selected. The material of the pipes should ideally match the material of the main line. The diameter of the regulator must be smaller than the cross-section of the main pipeline.

Ball valves are suitable for shut-off valves. They allow you to reliably shut off the coolant supply;
not worth installing mixing valve, which in normal wiring will not be useful;
installation of a control mechanism for single-pipe systems is considered necessary.

Before installation, the distance between the return and forward lines of the battery is measured. Then a piece of pipe of the required size is cut. This piece, in turn, is also cut in half and a ball valve is installed in it. In the case of using polypropylene pipes, crimping is carried out using the hydraulic method. Tees are cut into the supply and return branches and a prepared jumper is installed. To make it possible to replace radiators without draining the entire system, ball valves are also installed at the inlet and outlet of the device. Then the pipes are filled with coolant.

Note! The regulator operates using taps. One tap is mounted on a pipe. This is a ball valve that limits the water supply in an emergency. The other two cranes are mounted on horizontal lines.

The principle of operation of the bypass on the radiator

In a single-pipe design, installing a bypass for heating is necessary so that when replacing a heating device, the liquid continues to circulate. In a vertical installation, the radiator is connected to the riser pipes. The regulator combines the pipes and is mounted in front of the battery.

The functions of the jumper, which is placed in front of the radiator, include:

creation of constant movement along the main contour;
regulation of temperature and coolant flow directly in the radiator.

Installing a bypass allows you to mix the coolant from the central line with the return line of the battery. Due to this, the temperature and heating efficiency in general increases.

The nuances of strapping

It is important to understand what a bypass is in a heating system before installing one. Here are some useful recommendations that will help you do the installation yourself:

in order to direct the water in the right direction, the cross-section of the jumper must be smaller than the cross-section of the main pipeline;
the structure is installed next to the heating device, but as far as possible from the riser;
the taps are mounted between the battery input/output and the control jumper;
used to automate the temperature of the device;
When installing the structure next to the boiler, overheating must not be allowed;
tees are mounted on the sections of the main line;
Do not install a valve or valve on a valveless device.

When installing the unit, you must comply with building regulations. Near the bypass device there must be fastenings or special supports for pipes.

Bypass for circulation pump: importance of installation

To minimize heat loss, the use of a bypass in the heating system is required. What it is and why it is needed needs to be found out before using a forced heating system. The pump must be installed on the bypass and not on return pipe. Installation is also required, which is needed to prevent changes in the direction of movement of the coolant.

When installing, be sure to consider the following points:

For a forced heating system, a regulator is required so that when the power is turned off, the circulation of the coolant does not stop;
the cross-section of the regulator for piping the pump should be half the diameter of the main line;
A dirt filter must be installed in front of the pump to protect the reliability of the equipment.

Ball valves are used as shut-off valves for smooth adjustment of the coolant.

Related article:

This unit is installed in most closed heating systems, so it is extremely important to know how to select and calculate it correctly. Our review will help you!

Bypass valve: what is it?

The heating system often uses bypass mode. The diagrams presented above will help you understand what kind of mode this is. Installing a valve allows you to eliminate problems that arise when air appears in heating devices.

Bypass design with valve helps:

increasing network efficiency and minimizing space heating costs;
ensuring smooth distribution of coolant.

Equipment with a check valve is used to operate circulation pumps. When starting, the valve opens, allowing some of the liquid to pass through. After the pump is turned off, the valve closes and prevents liquid from flowing in the opposite direction. If there is no electricity, then the valve shuts off the coolant supply to the pump and opens it on the main line.

How is underfloor heating used in the system?

In a residential building, heated floors are connected to a boiler, which supplies hot water and heating. In this case, the water temperature for all structures will be equal. To ensure that the water is not so hot, special mixing units. To prevent a strong pressure surge, a bypass with a valve is installed in the unit. In this case, a three-way mixer is used to regulate the amount of chilled water. The water is mixed in the unit and moved to the water floor collector using a pump.

Related article:

Before starting work, you should study possible installation and connection schemes. A special publication on our portal will help you.

Installation in a small circuit of a solid fuel boiler

In the classic version of a single-pipe system, the bypass is mounted next to the radiators. When using solid fuel boilers for heating, the bypass jumper is often used for the entire heating system of the house.

Installation is carried out in the direction of the coolant:

a check valve is being installed, pumping equipment and filter systems;
installation of the unit in the main pipeline is carried out using couplings;
An additional tap is placed on the jumper, allowing, if necessary, to shut off the circulation of liquid.

Installing a bypass is not considered labor-intensive if you carefully study the work and installation nuances. With the correct selection of components, the heating system will be more energy efficient and reliable.

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Heating systems are made from a wide variety of components, and not all of them are equally familiar to people. If the function of a boiler, pump or regulator is generally clear, then the idea of a bypass is more vague. Meanwhile, the significance of such equipment, its right choice and consideration of features during installation are very large.

What it is?

It is not difficult to understand that even initially insignificant defects in the operation of engineering systems and communications can turn into serious problems. The discomfort and even danger to health caused by heating malfunctions can hardly be overestimated. That’s why attentive, thoughtful homeowners should be busy preventing such problems. The bypass, which is widely used in heating circuits and plumbing systems, plays a significant role in it. Its design is not particularly complicated - it is just a jumper in the form of a pipe, supplemented with control devices.

The bypass valve allows fluid to pass through ( drinking water or coolant in the heating system) away from one or another technical unit. Quite simply, this is a workaround for water in case of unforeseen situations. If everything works normally, the flow moves calmly and measuredly along the jumper. But under certain conditions, the locking element closes and the liquid rushes away from the previous trajectory. This effect is achieved because the diameter of the bypass is invariably smaller than that of the pipe that supplies water to it.

The use of such a device allows:

make service work on pipelines much easier;
increase the efficiency of equipment;
reduce unproductive energy costs;
radically solve the problem of filling pipes and other water infrastructure with air;
guarantee relatively stable performance even in unusual situations.

Sometimes you may come across arguments that installing a bypass is unprofitable. In fact, this is not so - when installing such a device, you can significantly save energy. The reduction in water supply to the batteries is up to 35%, and therefore it is possible to reduce thermal energy consumption by approximately 15%. Since many real systems consume a lot of heat, there will be no negative consequences. A more detailed picture can be understood in consultation with specialists.

Kinds

The wide range of uses has forced designers and engineers to create a wide variety of equipment for specific purposes. The differences between bypasses are determined either by the type of shut-off valve or by the intended purpose. Products with a tap belong to the mechanical group. All control of such a device is carried out manually by manipulating the tap, located mainly in the central part of the jumper. It is possible to use both three-way and ball shut-off devices; this does not affect the principle of operation.

The bypass line can also be made using a valve. This is a device that is completely autonomous from people and is not regulated during operation. The rubber from which the ball-shaped valve is made gives it excess buoyancy. This technique is usually used in direct connection with a pump that circulates water. Connecting them to each other allows for simultaneous launch.

Despite the convenience and ergonomics of the automated scheme, it is not applicable everywhere. Such devices may only be used in circuits with impeccably clean liquid. Inside the old one metal pipe Scale, rust, scale and foreign impurities are often found. If they come into contact with a soft valve, they can very quickly damage it. And the inability to completely open or close the fluid flow will deprive the automatic circuit of its main advantage.

The radiator type of bypass (with or without a surface-mounted thermostat) involves installing them next to heating batteries, which allows you to disconnect such batteries if necessary. Another type - pumping, is always installed next to pumping devices and, along with a complete stop, makes it possible to adjust their operating mode. It may be necessary to completely block the operation of a particular component in order to repair or replace it. In this case, the water flow will pass freely through the bypass, connecting the remaining radiators and the boiler (or parts of the water supply) as stably as possible. Also, backup power systems have to be used to overcome the objective weaknesses of a single-pipe heating system.

In it, the coolant is inevitably distributed in an insufficiently uniform manner. For objective reasons, sequential feeding of radiators results in cooling of the liquid, and even in the latest heating devices it circulates with very low efficiency. But if a bypass is mounted before the radiator, the problem is somewhat mitigated. A certain portion of the heated water reaches even the farthest corners without loss of heat and returns quietly. This advantage is especially valuable in extremely long and branched circuits.

In a similar way, it is possible to regulate the thermal output of radiators even in two-pipe systems. All you need is to turn off the tap in a certain place. Then the coolant will flow only to areas where it is needed. A bypass is also installed in those houses where the power supply is unstable. Closing the tap that supplies liquid through a temporarily idle pump allows you to restore the stable operation of the system as a whole. Yes, natural circulation is less effective than artificial circulation, but in such a situation you don’t have to choose.

The ball valve in the bypass is closed when required:

repair the pump;
replace it after breakdown;
Clean dirt from the filter mesh.

The bypass injection circuit is small in size and designed specifically for systems installed in a small area. The valve type is always made of a standard size; in such a bypass, the built-in pump, filters and taps are arranged in a straight line. Please note: it is prohibited to install bypasses with pumps if the boiler already has its own circulation source. The formation of a parallel outline is carried out in accordance with the requirements of SNiP. These standards must be taken into account when selecting components, down to minor details.

How to choose?

There is no doubt that a bypass is really needed for domestic purposes. However, in order to meet your expectations, you need to carefully select the appropriate equipment and take into account all the nuances. Automatic valves and conventional taps can be either in a short or an extended device. Their diameter is either DN40 or DN50. It is advisable to supplement water system a bypass in front of the measuring units, which will allow you to receive water even when the meters are dismantled.

Connection diagram

For the bypass to work properly, it must not only be selected correctly, but also installed correctly. Usually, one end of the bypass pipe is connected to the supply pipe, and the other to the outlet circuit. The section from the bypass to the inlet is equipped with locking parts, which either finally transfer the flow in the other direction or divide it into two parts. In order to completely shut off the liquid supply to the equipment, the valve is mounted on the outlet pipe. The simplest option is a pipe with tees connected on both sides.

Such uncontrolled bypasses have a continuously open lumen. In most cases, such devices are needed to supply water to radiators. Since it invariably moves along a route that has minimal hydraulic resistance, the cross-section on vertical products should be smaller than that of the main lines. Bypasses intended for lower distributions are formed with the same diameter as in the main section, and only the outlet pipe is reduced. It is recommended to rotate the ball valves from time to time to prevent them from blocking during prolonged inactivity.

In addition to calculating the distance, you need to take into account the fact that shut-off valves cannot be installed on bypass jumpers in multi-story buildings. If handled carelessly or automatically triggered, other heat consumers may be disconnected from the mains. But such equipment must be installed next to the pump that provides circulation. Radiators connected to manifold and two-pipe wiring options should not be connected to bypasses, since there is no point in this. Pumps are connected to the bypass if the system is designed for natural water movement.

In such cases, the following are of particular importance:

acceleration manifold;
compliance with the design slopes of the highway;
required clearance of any pipe.

The choice of wiring is determined by whether there is free space. The bypass when creating a warm floor is an integral part of the mixer. To prepare the coolant, you need to use a mixing block with three-way valves that allow a strictly limited volume of water to pass through. The rest of it is discharged through the bypass, after mixing with the cold liquid leaving the collector, and then moves towards the boiler. Of particular importance is the bypass in the heating main, where the solid fuel boiler supplies hot water.

There he helps create a small circulation circuit in the harness. The bypass channel is connected to the supply line with the most heated water; the other section is connected to the three-way return line valve. Therefore, water is returned to the boiler, which is heated to at least 50 degrees. The reason for this decision is to prevent rapid corrosion, which often overtakes boilers powered by wood or coal. Separately, it is worth mentioning the dead-end heating system and the introduction of bypasses into it.

The dead-end option is one of the varieties of the two-pipe circuit. The rings that are used for circulation have very different lengths. Their configuration is divided into vertical and horizontal formats. The vertical is created by including each device in a riser oriented from top to bottom. The closer the rings are to it, the shorter they are; the downside of this solution is the heterogeneity in the speed of water circulation.

Therefore, in its pure form, such a system is not capable of heating parts of the house in exactly the same way. Practicality is in question, and this solution is acceptable (no more) only in an apartment building. A horizontal dead-end system is formed if a direct and return pipeline is connected to the heating devices. The dimensions of the connecting units and the pipes themselves are exactly the same, which significantly simplifies the work of designers and installers. In addition, the horizontal design reduces the consumption of materials, but somewhat complicates balancing the operation of the radiators.

In any case, the dominant pipe is removed from the heat source. Through it, the heated liquid penetrates into the compensating tank, where there is a drain and a signaling pipe. The bypass is mounted either at the inlet to the boiler or at the outlet from it. This is determined by the project requirements. The tank serves to discharge the upper pipeline, from which liquid flows through the wiring towards the individual radiators.

Installation

One of the key requirements - the narrowing of the jumper compared to the pipe to which it is connected - is already familiar. Violation of this rule will not allow the liquid to penetrate fully into a certain device. The bypass is installed as far as possible from the riser, but this requires maximum proximity to the device being serviced. It is prohibited to install jumpers in any way other than horizontally - this can lead to increased accumulation of air bubbles. Before starting work, 100% of the water from the system must be drained.

Often they try to install bypasses using welding machines. First, the mechanism will have to be removed, and after that, choosing the most convenient point on the pipe delivering water, make holes in this place. They are formed in such a way as to match the diameter of the jumper. It is first inserted as tightly as possible, and then welded. Now you need to install locking parts on the thread to which the radiator was previously connected. And finally, the heating battery is installed in its original place, where it must be included in the system and attached to the wall using brackets.

It is also possible to do everything with your own hands. Before starting work, you will again have to turn off the radiator from the system and dismantle it.

Then:

a bypass is screwed onto the inlet pipe using proprietary couplings;
opposite edges serve for fastening locking fittings;
transfer the fixation points of the dismantled device;
they place it on the newly allocated area;
connected to the system correctly, as follows from its design;
secure the battery using brackets.

Given the great complexity of modern heating systems, it is recommended to entrust the installation of bypasses to professionals. It’s even better if everything is done at the same time as installing or replacing other components. High-quality installation necessarily includes crimping after assembly, since only this procedure will show whether all the work was completed correctly or not. But at the same time, self-installation should not cause special problems. The main thing is to carefully calculate everything and eliminate mistakes.

It is advisable to use completely finished products or form them from separate blocks. When there is no experience, it is advisable to choose ready-made designs, this reduces the risk of errors. In principle, you cannot place the bypass directly on the riser, but being too close to the heating equipment is too bad. Then the operation of the device will be disrupted, and its effectiveness will be insufficient. Directly at the bypass there must be positions for support or ready-made fastenings.

Excessively removed fasteners when heated rotate the pipe and make it unsightly in appearance. If it is necessary to revive the old heating circuit, install a bypass unit with a pump that provides circulation. Additionally, you will need ball valves (that do not reduce the speed of fluid movement) and check valve. Maximum attention should be paid to the selection of locking fittings and determination of the diameters of the working parts. A pair of tees and ball valves are mounted on each bypass pipe.

When getting acquainted with a certain device, you need to focus on its intended purpose. This determines whether a control valve, thermal regulator or return valve is required. All parts must be installed along the flow of water, counting from the filter. They carefully check that the parts are of high quality and work smoothly. The appearance of pores, especially large irregularities in the weld, is unacceptable; The parts connected using threads are normally unscrewed and dismantled without any extra effort.

The bypass will work more stable if it is supplemented with a filter.

Filtering is required:

when using hard water to transfer heat;
in a system that has been used for a long time and is worn out;
in the heating circuit where expensive pumps, boilers, radiators or pipes are connected.

In addition to rough mechanical cleaning, in many situations a more thorough, scrupulous preparation of water in the heating system is required. Of course, there is no particular need to install fine filters there that trap dirt up to 100 microns in size. But magnetic traps that prevent the spread of scale and rust will turn out to be quite useful devices. They can be mounted either with an insert into the pipe or externally. You can limit yourself to horizontal contours only in a one-story building.

As for the use of bypasses in apartment buildings, they bring no less benefit there than in private housing. Thanks to this device, the rate of change in battery heating increases significantly. They can be configured more flexibly and freely. This excludes a situation where it has already become warmer outside, but the central network has not yet had time to react to this, and supplies heat as in the recent severe frost. If regulators are used in the heating system, bypasses also turn out to be useful, they reduce the destructive effect of water pressure.

A one-pipe heating system requires a jumper in any case, but in a two-pipe design it turns out to be a redundant link. Radiator units or plumbing fixtures are installed independently. If you disable any of them, the other components will work as efficiently as before. The only exception is the use of three-way thermal valves. But such a scheme is used extremely rarely, because it is economically unjustified. Do not confuse a two-pipe system with the presence of two risers; this is not always related to each other.

In a real two-pipe circuit, the radiator inlets are connected to mutually autonomous risers. If the radiator is connected to a break in a single pipe, the second one goes on its own and is needed for the supply vector from above. This is only a riser, and the single-pipe system will not cease to be. Accordingly, the bypass turns out to be an absolutely necessary element in this case. Single-pipe circuits are often created in order to save money in private homes, for example, “Leningradka”.

It is not recommended to install any fittings in the gap from the riser to the bypass; such an arrangement can lead to accidental blocking of the main heating line. There are often complaints that moving the regulator away from the pipe and bringing it closer to the battery causes unpleasant aesthetic effects. But such claims are incorrect, because disguising the bypass is not particularly difficult. And strict adherence to technical standards turns out to be extremely useful in maintaining the functionality of the system. It is thought out in advance where the ball valves that isolate the radiator or thermostats will be installed.

The nominal diameters in the passages of heating risers are supposed to remain unchanged from the outlet to the tee into which the bypass is planned to be installed. The diameter of the pipeline supplying liquid to the radiator, in the area from the tees, is designated as DN2. Standard rules stipulate that the pipes here should be larger than the size of the riser. The bypass itself is one size smaller than the supply circuit and two sizes smaller than the riser. But the proportions described refer to uncontrolled devices.

The tee will divide the water flow into the main branch going to the radiator and the bypass branch passing through the bypass. If the system is equipped with thermostats, the jumper allows you to discharge excess coolant. This allows you to escape from excessive pressure and unusual vacuum. A bypass can be used to adjust the flow of water or to stop it by installing a tap. But in multi-apartment housing, such a configuration is unacceptable.

Adjustment in single pipe system Heating of a private house cannot be achieved with ball valves. This problem is solved by needle valves, which change the flow intensity as accurately as possible. An alternative is to use a control valve. When it is configured, even the most powerful random impact will not affect the operation of the system. In most cases, vertical risers are placed at right angles.

But instead, you can install a branch at the same angle with a diameter identical to the diameter of the riser itself. To connect a metal pipe to a polypropylene section, threaded fittings are usually used. In the space between the axis of risers and bypasses you can install polypropylene pipe with an outer diameter of 3.2 cm. At the inlet, the tee is designed for precisely such pipes. The tee output allows you to connect a 2.5 cm pipe, and the circuit connected to the bypass - 2 cm.

It is quite difficult to purchase a part with the necessary linear characteristics. However, there is a way out: you need to take the most common type of tee 25-20-25. An adapter is welded to the input, allowing you to connect a pipe with an external cross-section of “32”. It is undesirable to make a very large segment for the connection to the radiator; in many cases it is reduced to zero. The bypass in such a system is made from a 2 cm pipe, and then there are fittings connecting the welded joint of polypropylene to the metal.

Fittings are attached to the radiators to help connect the “American” style union nuts. There is usually no additional need to purchase such elements; most often they are included in the delivery set of thermostats. When it is planned to use a shut-off valve, it should be the same - with a fitting and a screw-on nut. This simplifies installation, while at the same time achieving a removable connection. Metal-plastic pipes and connecting fittings are connected using similar principles.

There are a number of schemes with which you can organize the entire circuit exclusively from metal pipes. Welding is still used for this purpose, but its popularity is steadily declining. There are almost always enough mass-sold parts with thoughtful threads. If the center distances of the radiators meet the standards, you can simply buy a fully completed bypass, which is already equipped with threaded sections at the factory. There are a number of bypass units on sale that help to deploy hidden connections and connect batteries from below.

In many cases, a decision has to be made without selection ready-made scheme, simply according to the characteristics of the place. The height of the lintel is not regulated by any standards or everyday practice; it is determined individually. Pumps on bypasses, if any, should be surrounded by taps on the right and left. This measure allows you to freely dismantle the device when the need arises. The jumper must also be installed on the “warm floor” collectors or on the “comb” of the supply and return collectors.

The purpose of its use is not so much to turn off the water as to exclude:

pressure surges;
water hammer;
sparse areas.

The pump, while creating overall pressure, is not flexible enough. All circuits must be supplied with coolant separately. Balancing valves can theoretically operate themselves, but it is the bypass that helps dampen negative impact pressure changes. Solid fuel boilers are equipped with bypasses due to the irregularity of their work, since the high temperature at the time of warming up creates a colossal load on the heat exchanger. It is for this reason that jumpers are used to reduce the duration of the warm-up cycle.

The three-way valve, having blocked the access of liquid to the external circuit, allows it to move strictly through the bypass, therefore the warm-up time is minimal, as is the risk associated with it. As soon as the small circuit reaches a certain temperature, the tap automatically systematically opens the inlet from the return circuit. The circulation slowly covers the coolant contained in the common circuit. Everything happens exactly as smoothly as possible, automation and mechanics coordinately control this.

Changing the bypass pump is done as follows:

the valve on the main line opens, the valve on the pump closes.
the pump is unscrewed from the complex, another is mounted;
the supply of coolant is resumed;
after unscrewing the screw on the front of the device, air escapes;
the valve mounted on the bypass line closes.

The operating time will be reduced several times, so you won’t have to stop heating. The use of bypasses not in heating, but in water supply circuits deserves special attention. Then they make it possible to simplify the switching of the water supply to hot water replenishment from the water heater. Depending on personal preference, you can even serve it on a cold tap.

Buying a simple bypass will cost 1200-1300 rubles; cheaper options cannot be considered high quality, since they are almost always defective or products of dubious origin.

If the house has old-fashioned cast iron batteries or steel convectors with fins, they are designed for the most part to operate without jumpers. In such cases, you need to carefully calculate everything and collect as much information about the system as possible. Mixing water is advisable not only when using solid fuel boilers, but also when placing air heaters. Bypass installation on heated towel rails is done in approximately the same way as in hot water supply. Technical features devices are subject to similar requirements.

A common mistake is to install the circulation pump outside the bypass. In this configuration, he has to push the coolant not only through the shut-off valves, but also through a pair of outlets. Thermal efficiency therefore drops sharply, and energy consumption and noise generated by the pump increase. There is a ridiculous myth that the circulation equipment on the bypass of the main riser will not work. In fact, the situation is the opposite: if there were no backup circuit there, it could not work.

Guided by this myth, some home craftsmen place the pump in the return bypass, placing a ball valve between the two inlets. Such a measure leads to the fact that before starting the pump the tap will have to be locked, and when stopped, it will have to be unlocked. And if you ever forget about this, serious problems will arise. If you install a standard check valve (with a spring), it will work poorly or not at all in this configuration, since the hydraulic resistance is excessive. You should not open check valves by removing springs from them or rearranging these parts.

Once you launch a system with such equipment, “original acoustic effects” and just squelching will quickly become apparent. The faster the coolant moves, the more often extraneous sounds will be heard. The most effective way The arrangement of the heat pipeline involves the use of a float check valve for the gravity system. Similar mechanisms are present in the assortment of almost all major companies producing components for heating systems. When the equipment operates in natural circulation mode, the float opens and does not block the flow of coolant; As soon as you start the pump in the bypass, the valve clogs the main riser and redirects the liquid along the bypass.

Attention should be paid to consumables and shut-off valves, such as valves. Faucets equipped with a movable stem have an important drawback - the diameter of the seat is almost 50% smaller than the diameter of the heating pipe. This circumstance significantly reduces the quality of circulation, therefore it is not recommended to install taps of the mentioned type in bypasses. In order not to suffer from this and not to open ball valves manually all the time, you need to use bellows valves with a twice the cross-section. It is much more difficult to select suitable fittings for the central channel, parallel to which the bypass is located.

They need valves various types, ensuring normal hot water pressure and quality. If the coolant is not very good, it makes sense to mount the filter on a horizontal sector of the pipeline. Placing it on vertical fragments does not justify itself.

In any case, you should give preference to valves from well-known, long-established manufacturers. To prevent problems associated with pipeline overflow with air, it is recommended to install a Mayevsky valve.

Mechanics should not get too carried away with welding, threaded connections much more practical and convenient. This will become even clearer at the first serious failure or during repairs, when the threads can be removed with bench tools, and it will be almost impossible to remove the welded parts. When choosing nuts, you can buy fasteners with gaskets made of both rubber and silicone. When removing and replacing a valve, you need to screw the coupling and locknut onto the thread, after which a piece of pipe is removed from the valve. This work is performed using open-end or gas wrenches.

Bypasses can also be used in water supply circuits, but their role there is much more modest than in heating products. There, jumpers are intended only to help in installing meters and pumps. Instead of measuring the section of pipe that needs to be cut and installing the finished unit on its basis, you can do it differently. The assembly itself is disassembled into parts, the pump is removed and the pipeline segments are connected to the main pipe. Then they reattach the pump and begin to work on the outlet pipe.

The pipeline is carefully lifted upward to prevent physical contact with pump. After this, it is either tied tightly, or a pair of pipes are sent on opposite courses. A tap with a jumper surrounding it is installed between these pipes; A similar technique allows you to build bypasses with your own hands for other plumbing fixtures. Of course, the hot water redirection unit must be designed and created so that it does not interfere with the work of the security team. That is why, despite the absence of visible difficulties, it is quite justified to turn to professionals for help in preparing and installing bypasses.

Using a bypass, all the main elements are installed in the gas pipeline and heating system of a private house. This simple design can facilitate repair and preventative maintenance of communication devices connected to the main line, and also increases the efficiency and efficiency of the heating system. This element in the form of a piece of pipe allows you to solve various problems and therefore is an important part of any scheme.

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General information

A bypass bypass is a pipe used to pass coolant around a specific section of the heating system or parallel to it.

Typically, this location contains some kind of communication device. One end of the bypass pipe in the heating system is connected to a suitable pipe, the other to the outlet pipe.

Between the bypass pipe and the inlet pipe of the bending device it is necessary to embed shut-off valves. It makes it possible to completely direct the flow of coolant through an alternative pipeline or adjust the volume of incoming water.

To make it possible to completely turn off the equipment, shut-off valves are also installed on the outlet pipe - between the bypass and the outlet of the device.

A bypass is needed in the heating system. Installing this device provides many benefits:

maintenance of the heating system is facilitated;
with a significant number of batteries, the overall efficiency increases and energy consumption decreases;
the problem with airing of pipes and radiators due to their depressurization is solved;
You can use the equipment even in emergency situations.

HOW TO MAKE A BYPASS FROM A PROPYLENE PIPE

Main types

Shut-off valves must be installed not only on the inlet and outlet pipes, but also directly on the bypass in the water supply system. Taking into account the type of equipment used There are several types of bypass pipes:

automatic;
with mechanical control;
unregulated.

All types of bypasses have certain features of use and design.

Fixed bypass pipe

An uncontrolled bypass installation in a heating system is a simple bypass pipe without additional devices. The lumen of the pipeline is always open, and the flow of water occurs in an uncontrolled mode. These bypasses are most often used when connecting batteries.

When designing a heating system, it is necessary to take into account that the coolant will flow with minimal hydraulic resistance. Therefore, the flow area of an unregulated bypass pipe, which is installed vertically, must be smaller, in contrast to the diameter of the main line. Otherwise, under the influence of gravity, the coolant will begin to flow into a nearby bypass.

The horizontal scheme works on different principles. The hot coolant tends to the top because it has a lower specific density. Therefore, the bypass for lower wiring, as a rule, is set equal in cross-section to the main pipe of the main line, and the pipe leading to the battery is smaller.

The reduced cross-section of the incoming battery pipe increases the coolant pressure, which promotes uniform circulation of liquid along the circuit.

A bypass pipe with a ball valve is called a manual bypass. This valve is ideal for bypassing the coolant route, since in the open position it does not reduce the internal diameter of the pipes.

Accordingly, it does not create resistance to flowing water. The use of a locking mechanism makes it possible to control the volume of fluid that passes through the bypass. If the valve is closed, the entire flow of coolant will flow through the main line.

It must be remembered that the working elements of these cranes tend to stick if the equipment is not used for a long time. Therefore, the tap must be turned regularly, even if it is not necessary.

The scope of use of manual bypasses in a heating system is piping circulation pumps and connecting batteries in a single-pipe circuit.

Bypass where to install and where not.

Automatic designs

This bypass is used for circulation pump. An electric pump is installed in the system to increase the speed of water movement, this reduces heat losses, ensures uniform heating of the premises, and increases overall efficiency.

The direction of the coolant flow in the automatic pumping system is carried out without human intervention. While the pump is running, water flows through it and the bypass closes.

If the pump stops as a result of failure or power outage, water begins to flow through the bypass. The impeller of the device limits or closes the movement of the coolant.

Automatic bypasses can be of several types:

injection;
valve.

In the latter case, a check valve is installed in the bypass pipe, which creates minimal resistance and almost does not interfere with the movement of water in gravity mode.

When the pump is turned on, the flow rate increases. The coolant from the outlet pipe passes into the main line and moves in both directions. Then it passes unhindered along the contour, and while moving back it rests against the check valve.

Since the pressure at the outlet pipe is greater than that at the inlet pipe, the ball is pressed against the seat and closes the lumen of the pipeline. The disadvantages of a valve bypass include sensitivity to water quality. If dirt gets in, it will break.

The injection bypass operates on the principle of a hydraulic elevator. A pump with a smaller diameter at the outlet to the pipeline is connected to a large cross-section pipeline. When the pump is turned on, part of the flow enters the diffuser of the inlet pipe and passes through this device, receiving acceleration.

The outlet pipe has a small narrowing, representing a nozzle, through which the coolant under pressure enters the main line at high speed. A vacuum is created behind the cut of the incoming pipe. Thanks to this, water is drawn in from the bypass. So the entire flow accelerates further along the highway. This directed movement of water prevents reverse flow.

Transfer of hydraulic fracturing to bypass

Purpose of the bypass section

Any device that is connected using a bypass can be removed from the main line by simply closing the inlet and outlet taps. After this procedure, all water flow will begin to pass through the bypass pipe.

A device that is disconnected from the mains can be easily repaired or the necessary maintenance performed. Moreover, you do not need to turn off the entire system or drain the water completely.

In a private heating system bypass pipes are used in the following cases:

Taking into account the place of use, connecting the bypass with your own hands has certain features.

For heating batteries

Batteries are connected using a bypass only in a single-pipe connection scheme. For collector and two-pipe wiring, inserting bypass pipes does not make sense. In this case, the radiators are connected in parallel and each one is supplied with a coolant of the same temperature from the main line. A breakdown of one of the heating circuits when installing shut-off valves will not affect the operation of the entire system.

With a single-pipe circuit, as a result of the series connection of the batteries, the water is cooled taking into account its passage through the circuit. The greater the heat transfer from the radiator, the colder the coolant will be at the outlet.

If there are no bypasses in a single-pipe circuit, then the first battery will take the greatest amount of heat, and it will go to the last cold water.

When connecting pumping equipment

It makes sense to connect the pump using a bypass only in a system that is adapted for gravity flow of coolant.

The collector must be installed, all required slopes must be made and a pipeline of the required cross-section must be installed. A pump in this system is required to improve the operating efficiency.

If the heating system was originally intended to be forced, then during a power outage or pump failure it will not work in any case. Water will not be able to circulate without distillation equipment. Therefore, with this wiring diagram, the pump is mounted without a bypass - directly on the main line.

The main feature of connecting a pump using a bypass is the possibility of a counterflow occurring in the bypass and the appearance of a vicious circle of fluid passage along the pump-bypass circuit. Therefore, the bypass pipe must contain a shut-off valve - a check valve.

The liquid in the main line can reach up to 85 °C, and in the water floor circuit - no more than 50 °C. To prepare the coolant, a mixer with three way valve, allowing only the required volume of hot water to pass through.

Another stream enters the bypass, mixes with the cold liquid leaving the manifold and is sent further through the main pipeline to the boiler.

Installation features

Bypass installation various types the heating system has certain features. When connecting radiators:

It is prohibited to install a tap on the bypass in multi-storey buildings;
the jumper must be placed as close to the battery as possible;
the cross-section of the bypass pipe is selected to be a size smaller than the main pipeline.

Installing a bypass on batteries can be done both when installing a new heating system, and during the modernization of an existing one. To do this, you need to prepare pipes of the required cross-section, shut-off valves and 2 tees.

On the inlet pipe You can install one of several equipment options:

A shut-off or ball valve is mounted on the outlet pipe. All parts are connected to each other by welding or threading. It is necessary to ensure the tightness of the connections, perform a test run after installation and eliminate leaks.

When connecting the pump, as a rule, the bypass is part of the main line. Since it ensures the passage of water in a natural mode, it is prohibited to narrow its internal cross-section.

For installation, it is most convenient to buy a ready-made pump unit of the required configuration. This will allow you to correctly position all the elements and ensure the reliability of the joints.

A fairly simple engineering device - a bypass - makes it possible to make the heating system more efficient and achieve the necessary thermal regime in a house or apartment. Failure of individual parts of the main highway or power outage will not cause significant problems. Hot water will circulate, and the rooms will be constantly warm.