Why do you need a sewer pipe. Proper installation of a fan sewer in a private house Fan riser on the roof

Eco-friendly homestead: Competent arrangement of the sewer system requires special knowledge, accurate calculations and understanding of the features of the designed structure. There are no "optional" elements in such a system. Nevertheless, quite often you can hear from unfortunate specialists that the fan pipe is an extra part of the structure. Let's figure out why this element is needed and whether it is possible to do without it.

Proper arrangement of the sewer system requires special knowledge, accurate calculations and understanding of the features of the designed structure. There are no "optional" elements in such a system. Nevertheless, quite often you can hear from unfortunate specialists that the fan pipe is an extra part of the structure. Let's figure out why this element is needed and whether it is possible to do without it.

A fan pipe is a section of a sewer pipeline that extends from the riser and ends outside the house, at outdoors. Most often, such an element is displayed through the roof and rises above the roof. The main role of the fan pipe is to maintain normal pressure in the sewer system, which is very important.

All plumbing fixtures are equipped with a water seal, which is located inside the siphon. This is the name of a structure that holds a certain amount of water inside. It becomes a kind of lock that prevents gases from the sewer from penetrating into the room. If the siphon works normally, there are no unpleasant odors in the room. But in some cases, the water seal can be broken. This happens when the pressure in the sewer system decreases sharply, and the water from the siphon is literally sucked out.

The most common reason for this phenomenon is the massive discharge of wastewater. The simultaneous appearance of a large amount of discharged liquid in the sewer system leads to a sharp drop in pressure and, as a result, to the breakdown of hydraulic seals of plumbing equipment. fan pipe or pipes, if the length of the sewer is large, communicate with the atmosphere, which stably normalizes the pressure.

Thus, the installation of a fan pipe is necessary if a one-time drain of all plumbing fixtures installed in the house can block the cross section of the sewer pipe. You need to know that a 110 mm fan riser is always used for the toilet. This is due to the fact that a 70 mm pipe is usually mounted on the drain, rarely more, so when flushing one toilet bowl, the drain will not be blocked. A pipe with a diameter of 50 mm usually departs from the bath, since the through hole of the siphon used here is always smaller. One-time drains of other plumbing fixtures are much less.

To determine the total maximum value, they must be added. Practice shows that in one-story small houses if there is no more than one bathroom, a one-time drain is unlikely to block the cross section of the sewer pipe. Therefore, it is possible to install the system without a fan riser. SNiPs stipulate when the arrangement of a sewer without a vent pipe is prohibited. It must be present in houses with two or more residential floors, each of which is equipped with plumbing and sewerage. The fan riser is installed without fail if an autonomous sewer system is located near the house.

If the housing is equipped with risers with a diameter of 50 mm, if the building has a swimming pool or any other structure that produces a large volume of one-time drains. In addition to stabilizing the pressure in the system, the fan pipe performs another role. It ventilates the sewers, removing unpleasant odors. For this reason, it must end in a place where sewer gases can be easily vented to the atmosphere.

Most often, the pipe is brought to the roof and ends at a height of about 0.3-0.5 m from the level of the roof ridge. It is very important that the diameter of the fan riser is the same or slightly larger than the cross section of the sewer. Only then will the system work effectively.

According to SNiPs, the fan pipeline should be laid only in a warm room. If this is not possible, high-quality insulation is carried out, otherwise the pipe will freeze in cold weather, which will lead to a deterioration in the operation of the system. In addition, the upper part of the element already in the first year of operation in such conditions will be covered with an unpleasant coating. Subsequently, its quantity will only increase, which will lead to damage to the part.

Experts recommend bringing the fan pipe as close as possible to the ridge, which will protect it from snow drifts. All kinds of turns are highly undesirable. Risers should be as straight as possible to avoid unnecessary opposition to airflow. For multi-storey buildings with long internal horizontal wiring, several fan risers will need to be installed. Their exact number will be specified by the designers.

In buildings where sewage flows into autonomous system biotreatment, a fan pipe must be installed. This is because the aerobic microorganisms present in the system are vital oxygen. Its access is provided, among other things, by the arrangement of effective ventilation.

The fan riser can be metal or plastic. In the first case, a cast-iron sewer pipe of the required length is taken for its manufacture. This option is used for metal systems. The fan riser can also be made of a plastic pipe, this is the most common option. It can be used for both plastic and cast iron piping.

The arrangement of a fan riser is associated with certain difficulties: making an outlet through a wall or roof, increasing the length of the structure, etc. But the homeowner can be sure that the pressure in the sewer system will always be normal, and he will not be threatened with failures of the plumbing water seal.published If you have any questions on this topic, ask them to specialists and readers of our project.

In order for the sewer system to work properly, it is necessary that it communicate with the atmosphere. Owners of private housing, independently engaged in the installation of engineering systems of their homes, need to know what functions the sewer riser performs. Let's figure out what kind of device it is and how to install it correctly.

Many owners undertake to build the plumbing and sewer system of their home on their own. To do this, you must first study the theory. One of the mandatory elements of the system is the fan riser. Not everyone understands the purpose of this element and often underestimate its importance. Let's figure out what a fan riser is, why it is needed and how the installation goes.

Purpose

An integral element internal system drainage, connecting the wastewater disposal system with the atmosphere, is a fan riser. The main function of the element is to equalize the pressure inside the system and maintain water seals for plumbing items.

Advice! A water seal is a flexible drain in the form of a loop, installed after the drain hole of plumbing items. In the lower part of the bend, there is always water, which acts as a “plug” that does not let sewer gases into the room.

If there is no fan riser, then at the moment of discharge of a large volume of wastewater (for example, when using a flush in the toilet bowl) in the water seals of plumbing fixtures installed in the neighborhood, they can be disrupted.

After that, unpleasant odors coming from the sewer system will appear in the bathroom or in the kitchen. Thus, this is a kind of ventilation for sewage, it performs two functions at once:

• removal of hazardous sewer gases into the atmosphere;
• maintaining normal atmospheric pressure inside the pipeline, preventing the occurrence of vacuum and removing hydraulic seals.

Is it always necessary?

During the construction of a drainage system for an individual house, the installation of a fan riser is not always mandatory. Yes, during construction one-story house, equipped with a single bathroom, you can do without this element. But in the following cases, it will not be possible to do without a fan riser:

• the house has more than one floor, each floor has a bathroom;
• the sewer riser has a diameter of 50 mm;
• an object is connected to the sewerage system, for the maintenance of which it is required a large number of water, for example, a pool;
• a sealed system is used with the installation of an underground septic tank.

Device

We will figure out how to plan the device and installation of a fan riser. Installation should be planned during the design phase internal sewerage. It is desirable that the circuit be as simple as possible, it should have a minimum number of corners and bends.

The ideal position of the fan pipe is vertical, the pipe is led out through the ceiling and roof. However, in practice, sometimes it is not possible to maintain a perfectly vertical shape, it is often necessary to attach additional elements.

For example, it is not always possible to connect all taps from plumbing fixtures to one riser. Sometimes it is necessary to install an additional riser, which can be attached to a common fan pipe.

It is possible to install one fan pipe at an equal distance from two risers and connect them to this duct. This connection method allows you to evenly distribute the pressure in the system. One of the rules for creating a fan riser is the correct selection of diameter. It must match the diameter of the main riser.

Advice! It is not allowed to combine the ventilation of the sewerage system with the chimney or the ventilation system of the house.

Material selection

Since the fan riser is a continuation of the sewer system, it makes sense to make it from the same material as the sewer riser itself. However, if necessary, the use of a combination of materials is also allowed, although experts argue that the efficiency of such a heterogeneous system will be lower.

What types of pipes are used? In most cases, cast iron or plastic is used.

• Cast iron. This is a durable and strong option, but it has significant drawbacks. The most significant of the minuses is the significant weight of the structure, which greatly complicates their installation.
• Plastic. Now in most cases plastic pipes are used. They are lightweight, durable, strong, resistant to corrosion processes.

The choice of pipe diameter is carried out depending on the characteristics of the system. In most cases, in private houses, a pipe with a diameter of 110 mm is used to assemble the riser.

Mounting Features

The device of the fan riser is not particularly difficult. Temperature fluctuations contribute to the intensive removal of gases from the system, since the initial section of the sewer system is located in a heated room, and the fan pipe is located on the street.

The main part of the fan riser is a vertical section; care must be taken to securely fix the pipe. It is attached to the walls with metal clamps. The most difficult moment is the removal of the element through the roof.

The outlet of the pipe to the attic is unacceptable, and the placement of the outlet under the roof overhang is irrational, since the structure can be damaged during snow melting from the roof. For the system to work effectively, the following rules must be observed:

• sections of the sewer pipeline laid horizontally should be located at a slope of 0.02% towards the riser;
• it is forbidden to change the direction of the riser above the level of connection of the extreme outlet from the plumbing equipment;
• when connecting some branches of the pipeline, it is necessary to use bends with an inclination angle of 135 and 45 degrees;
• The height of the pipe above the roof depends on the structure of the roof. If it is an unused flat roof, then the height must be at least 30 cm. On a pitched roof, the pipe must rise half a meter or higher. If the fan riser is discharged through an operated flat roof, then you will need to use a pipe with a height of at least three meters;

• if the outlet of several pipes (chimney, ventilation, etc.) is organized on the roof, then you need to make sure that the fan riser is higher than all the others. Otherwise, unpleasant odors can enter the house;
• the outlet of the fan pipe should be located away from the windows, the minimum distance is 4 meters;
• do not install visors or other decorations on the fan riser. These parts will interfere with the movement of air, in addition, it will contribute to the accumulation of condensate, which will lead to the formation of a layer of ice and a decrease in the diameter of the passage. To prevent birds or debris from entering the system, simply tighten the top of the pipe with a grate.

Warming and soundproofing

We will figure out whether it is necessary to insulate the fan pipe and use sound insulation. The riser passing through the living quarters does not make sense to insulate. But the part that runs through the cold attic and above the roof must be insulated. Otherwise, ice will form inside in the cold.

But soundproofing, on the contrary, is necessary in residential premises. Previously, no one thought about soundproofing fan pipes, since the soundproofing properties of cast iron are much better than those of plastic.

In our time, when the cast-iron elements of the sewage system are practically not used, it is worth using sound insulation to increase the comfort of living. IN plastic pipes there is noise of a different plan:

• Shock. Noise occurs when water flows against the walls of pipes.
• Atmospheric. Sounds are created by air currents entering the system.
• resonant. Noise occurs when the sewer pipeline interacts with walls, floors and other building structures.
• Vibrating. This type of sound occurs if the pipe comes into contact with any operating equipment (most often pumps).

High-quality sound insulation can be done if you start building engineering systems at the design stage of a house. Then the laying of risers is carried out in specially created mines that will restrain the spread of sounds.

In the event that the pipe is laid openly through the living quarters, then sound insulation is carried out by wrapping it with polyethylene foam material in two or three layers.

Alternative

In a small private house, you can not install a fan pipe, its function will be performed by a vacuum valve. Let's figure out what kind of device it is and how it can be installed. The functions of the vacuum valve are the same as those of the fan pipe, that is, to prevent the occurrence of vacuum in the pipe and makes it impossible for unpleasant odors to enter the house.

Installing a vacuum valve in a private house is a complete replacement for a fan pipe, while its installation will be much cheaper.

Advice! It is important to distinguish between the functions of a check valve and a vacuum valve. They differ both in execution and in purpose. The non-return valve prevents back flow of fluid, and the vacuum valve ensures pressure balance.

The vacuum valve works due to the difference in pressure inside the system and outside. When a vacuum occurs, the valve opens and allows air to flow into the system. After equalizing the pressure in the system, the vacuum valve diaphragm returns to its place. However, this device also has significant drawbacks, namely:

• sticking of the membrane if the valve does not work for a long time, that is, this option is not suitable for houses with periodic residence;
• wear of the membrane with frequent opening and prolonged use.

From the foregoing, we can conclude that the vacuum valve must be changed periodically. However, this device is inexpensive, and its replacement is not a difficult task.

So, the installation of a sewage fan riser in a private house is mandatory if the house has two or more floors and there is a bathroom on each floor. In a small house, instead of a fan pipe, you can install a vacuum valve. The design and construction of a fan riser can be done independently, but if difficulties arise, it is better to entrust the work to specialists. Only after the installation of the fan pipe is completed, the work on assembling the internal sewerage system can be considered completed.

Creating a high-quality sewerage system in a private house eliminates problems with unpleasant odors that accompany work sanitary equipment. Therefore, the installed sewer fan riser in a private house will be an integral element of the household network.

Functional Features

With a sharp discharge of a large volume of water into a pipeline of small cross section, pipes often break, water hammer. Therefore, a sewer pipe for sewerage in a private house is an integral element of internal engineering networks. Due to its use, the sewerage system in a private house has an additional air flow, and additionally the design eliminates pressure drops.

An apartment building without a vent pipe can only function with the installation of a shower cabin, where the water flow is small. A standard bathroom refers to peak flow rates, during the discharge of wastewater from a sanitary appliance, the pipe section is filled to the maximum, fresh air becomes minimal.

A similar situation in houses without a vent pipe provokes flooding of the first floors of the building at the time of the mass draining of water. Installing an additional structure will extend the life cycle of the sewer riser, especially plastic, and will also even out the work of home ventilation in the sewer pipes.

Many craftsmen advise narrowing the diameter of the pipeline, citing the lack of costs in the attic of the house. Regulations, as well as experience in the operation of engineering networks in the private sector and apartment buildings forcing them to refrain from doing so.

Sewer pipelines from sanitary unit where the toilet is installed are dictating. The toilet drain pipe has a cross section of 110 mm, the household sewer riser must repeat its size or be larger. If two toilets and two bathtubs are installed on the riser, it is necessary to carry out a hydraulic calculation of the throughput of the riser.

Structural layouts

Modern solutions sewer network based on polymer pipes, allow you to significantly extend the life of the system and simplify installation work. Sewerage in a private house without a fan pipe remains quite working, especially in houses with a small number of appliances and people, the standard system copes with the flow of effluents.

An unpleasant odor appears at times of high load, when most of the devices work at one moment. In such situations, many owners install additional aerators - ventilation valves, they compensate for the lack of air in the system. Installation of such equipment occurs at a level of 1–2.5 meters from the level of the finished floor.

The installed fan complex will provide a number of advantages:

• Working and independent for removing odors from risers.
• Creation of a qualitative restriction of the inflow of water, with normalization of the air pressure inside.
• Providing functionality for several bathrooms located at different levels in a private house.

Such items will allow you to build the required riser, taking into account good ventilation and ensure longevity of functionality. The resulting sewerage will ensure the use of several full-fledged bathrooms.

This is relevant when private house has independent and multi-level options for the placement of wastewater. There is only one way out in this situation - the masters can mount the system with one fan riser, the exhaust part of which will be combined. But the diameter of such a pipeline must correspond to the cross section of the working riser or be 50 mm larger.

Pipe materials

A sewer pipe for sewerage in a private house with a height of two, three or four floors is a decisive factor; in its absence, hydraulic valves of the upper sanitary appliances must be calculated for an additional load. In this calculation, it is necessary to take into account the second flow rate from the devices, the pipeline cross-section, local resistance and pipe material.

Depending on the temperature of the discharged water, as well as the requirements for the working strength of pipelines, specialists select and install the following pipes:

• Plastic, modern polymer or metal-plastic for gravity lines.
• Plastic, metal-plastic pipes of low-noise series for pressure pipelines.

Structural solutions for the installation and removal of the vent pipe to the roof

When designing a house or carrying out reconstruction, it is important to choose the right location for the system and individual sewer units. Only in this case, the sewer outlet in a private house will function, regardless of the weather outside the window.

When it comes to a large temperature difference inside and outside the building, especially when the house is in use all year round, and the climate has a long period negative temperature, then the craftsmen install the node inside the building or connect electric heating.

Installation should be carried out inside the building, leading the riser above the level roofing. This will eliminate problems with freezing and give a reason to ensure the necessary functionality, regardless of weather conditions. In this case, the sewerage system will provide a number of regulatory requirements:

• Withdrawal bad smell.
• Condensation and freezing of pipes are excluded.
• Full functionality without water hammer at the time of peak flow.

In a situation where the owners of the house do not have the necessary free space for installing a fan node indoors, experts advise installing the node to outer wall, sew up the structure, insulate mineral wool. Additional source heat in this design is a heat cable.

Functional sewerage system without fan nodes

Sewerage in a private house without a fan pipe is carried out in one-story buildings with an operated basement, but the installation of a toilet bowl and a bathroom takes place only on the ground floor near the riser and outlet to the external sewer network.

The consumption of the washbasin or washing of the house system in this case is not dictating, such an amount of wastewater from sanitary appliances occurs irregularly and is not capable of affecting the operation of the system.

A private house is often equipped with grease traps, the equipment reduces the concentration of fats and organics in wastewater. Installation of such equipment involves regular flushing of pipes hot water. Air valves will help compensate for the lack of oxygen.

The valve outlet is connected to main pipeline from washing fittings, the difference in marks protects the equipment from flooding during flushing of the pipeline.

For owners country houses doing a lot for home improvement with their own hands, it is useful to know some of the features of the arrangement of water supply and sewer systems. These are the most basic engineering communications, without which the construction of any house is not complete.

When installing a sewer, it is important to remember about such a device as a fan riser. What is this device and what are the nuances of its installation? These and a number of other questions can be answered in our article.

The fan riser in a private house is a part of the pipeline connecting the sewer riser to the open air.

Fan pipe on the roof of a private house

In the absence of this element, during the development of wastewater in the system, rarefaction occurs, the water seal is broken, and the room feels bad smell. For each plumbing device be sure to have a drain pipe with a bend. In this bend, water is normally found. It also performs the function of a water seal, preventing the penetration of unpleasant fumes into the house. With a sharp discharge of wastewater in the sewer pipes, a vacuum occurs. Air from the street passes through the fan device into the system, and the pressure returns to normal. This ensures that there are no odors.

Sometimes you can do without a fan riser. For example, in a small building consisting of one or two floors. However, a mandatory requirement in this case is the equipment of only one bathroom.

If the house has two or more bathrooms or several toilets, then the installation of a fan riser is mandatory. Its presence is determined by the following factors:

Development stage

Even at the design stage, in order to install the sewer riser correctly, two basic requirements must be taken into account:

1. The sewer pipe must be led out in the direction from which the vapors are discharged due to air flows.
2. Simplified installation fan system can be understood as the supply of pipes to ventilation duct. If this is difficult, the outlet is carried out through the wall.

The ventilation structure for eliminating unpleasant odors consists of different parts:

• fan pipes;
• ventilation ducts;
• connecting elements;
• fittings.

Features of the work

Having dealt with what a fan riser is, you need to carefully study the principles of its installation. It is advisable to plan the installation of this device as soon as the development of the project of the internal sewer system begins. In order for ventilation to work better, you should try to avoid bends and corners in the structure.

Fan riser output diagram

The ideal position of the air riser is exclusively vertical. This pipe is led through the floors between floors to the roof. However, this is not always possible in practice. Often in country houses you have to use additional elements for connection.

Sometimes they use the method of connecting several risers into one duct. This can be connecting an auxiliary riser to the main one or removing a vent pipe with its connection at the same distance from two risers.

This installation method is better because it allows you to evenly distribute air pressure throughout the system.

Fan pipes on the roof of the building

One of the main rules of installation is the correct diameter of the air pipe. It should not be larger than the diameter of the sewer. At the same time, the indicator of this element ideally corresponds to the size of not only the central riser, but also the branch pipe, which serves to connect the external and internal sewers.

It is also worth remembering that it is unacceptable to combine sewer ventilation with any climatic design or outlet carbon monoxide during operation of the heating boiler.

How to change fan riser

If the air riser breaks down, it is often necessary to replace it. The replacement of the structure is carried out according to the same principle as the repair of individual sections of the sewerage system. This process differs mainly in the material from which the pipes are made, and in the method of their connection.

Fan pipe repair

To replace the fan riser, a number of conditions must be met:

1. During demolition work organize good ventilation in the living room.
2. Structural elements need to be replaced in a respirator and rubber gloves.
3. At the end, you need to make sure that all the pipeline was sealed.

By itself, the installation of a fan riser is not particularly difficult. Nevertheless, the masters recommend following some important requirements.

It is better that the diameters of the fan pipe and the riser match.

Fan cast iron pipe

If a combination of several materials is used in the work, for example, a plastic fan pipe and a cast-iron riser, it is recommended to use a rubber adapter.

For articulation of several fans, angles of 45 or 135 degrees are used. Sections of the fan system, located horizontally, must be laid with a slope of 0.02% in the direction of the gas outlet.

If it is required to change the angle of the direction of the pipe, a special bend with a degree of rotation of 135 is used.

Requirements that fan risers must meet

Certain criteria have been developed for air risers. During the installation of the system, it is advisable to check with them:

1. When the pipe is brought to the roof, it must rise above the roof by at least 30 cm.
2. If an attic or attic is built the minimum length of the pipe must be three meters.
3. The gap between the pipe and a nearby light opening or loggia is made in length at least 4 meters.
4. Fan system in accordance with existing regulations is carried out through rooms with heating or must have an individual insulation.
5. It is not allowed to lead the air pipe through the chimney.
6. The upper component of the fan riser is equipped with a protective grate, which prevents the penetration of insects and birds into the structure.

Common mistakes when installing a riser

Despite the fact that the installation of the fan system can be done independently, there are a number of nuances, the knowledge of which will help to avoid serious shortcomings in the installation of the riser.

Installation of a fan pipe

Sometimes incorrectly carried out work on the equipment of a funnel design has rather unpleasant consequences.

For example, the owners of country houses do not always correctly install the fan pipe, trimming the system immediately in the attic. This leads to the fact that unpleasant odors seep into the attic, which can also penetrate into the housing.

Another serious drawback is the installation of a fan on the outer wall. In this case, there is a risk of condensation.

Some owners prefer to mount an additional device - a roof aerator.

Pitched roof aerators

Its function is to improve traction. However, this is not always advisable. In most cases, the following happens: the outflow of sewer gases is weaker and an unpleasant smell from the bathroom can be felt in the house.

Installation of an air riser becomes a prerequisite for the correct equipment of the waste system. The absence of this device leads to rather negative consequences.

Sometimes it is better to entrust the installation of the pipe to qualified specialists. If you do not have the required number of tools or materials, you should not do the installation yourself. Buying the right equipment, which is unlikely to be useful to you in the future, does not make sense. In addition, the arrangement of sewer systems has its own specifics. An experienced master plumber will do the job efficiently, taking into account all requirements.

In order to correctly perform the installation, it is necessary to strictly observe a pre-prepared project and perform all the necessary calculations.

What can replace the fan pipe

An alternative option for ventilation sewer systems is considered to be vacuum valves. They are installed at the end of the sewer riser in the house itself.

Installation of a vacuum valve on a sewer riser

Inside the vacuum type valve is a special spring with low resistance and a rubber sealing element for tightness. The principle of operation of such a device is as follows:

1. Sewer drains, passing along the riser, provide a vacuum in the system.
2. The shutter or valve opens.
3. The air from the siphon is sucked in and passes into the sewerage network. This extinguishes the vacuum.
4. After normalizing the pressure in the sewer system, the spring mechanism comes into action. The valve closes the gap and does not allow an unpleasant smell to pass into the room.

In situations where it is not possible to install check valve sewers to the riser, this device can be mounted on any other segment of the horizontal pipe supplied to the riser.

Attention should also be paid to such important point, as the presence of a hydraulic shutter at each plumbing point.

Using a hydraulic seal

Otherwise, an unpleasant smell in the house cannot be avoided, despite the properly installed sewer system and ventilation equipment. Most modern sewer devices have built-in hydraulic seals.

There is a special document - a set building codes and Rules (SNiP). These requirements must be taken into account. The documentation contains the conditions for the mandatory equipment of fan risers:

• houses with two floors and above in which there is a sewerage system and installation of plumbing devices;
• in houses from autonomous sewerage , with the presence of a storage tank, a septic tank or cesspool;
• if indoors constant bad smell.

In any case, equip the air riser in country house necessary. Only in this way can the work on laying the sewer pipe system be considered correctly performed. No one wants to put up with the presence of sewer odors in living quarters. You can invite professionals to install the fan pipes, or you can try to cope with this task yourself.

Arrangement of ventilation of an independent or centralized sewage disposal system is impossible without the installation of a special fan outlet. The element blocks the return flow of gases to the bathrooms, acting as a connecting component between the septic tank and the atmosphere.

The installation technology of the riser is quite simple. But before you start work, you need to understand the principle of operation of the ventilation duct and understand how to properly install the fan pipe in the house. The answers to these questions are detailed in the article.

The fan pipe is a structural element that connects the pipeline to a specially erected ventilation duct. Its key purpose is to remove gases and odors distributed from the sewer.

The presence of a ventilation riser in the system guarantees the absence of unpleasant loud sounds in the living quarters that occur at the time of draining the water, and the “fragrances” of sewage sewage (+)

The length and shape of this element can be arbitrary. There are models of vertical and horizontal execution, beveled at a right or acute angle.

The principle of operation of the fan pipe is simple. Wastewater entering the vertical riser creates a vacuum in the cavity of the pipeline. It can be partially compensated by water, which acts as a hydraulic damper in the siphons of installed plumbing.

But if a vertically installed riser has a large length and at the same time at some point there is a one-time powerful discharge of the waste liquid, then in sewer pipe a vacuum occurs.

The piston formed from the liquid, with all its strength and a characteristic “smacking” sound, at one moment breaks and breaks through the plumbing valves, emptying the siphons.

As a result, water is completely sucked out of all water seals. Therefore, there are no obstacles left. Due to this, they quickly spread throughout the building.

This effect also appears with rapid pumping. fecal pump the contents of a cesspool or septic tank into the tank of a sewage machine

The trouble is that the appearance of an unpleasant "fragrance" in living rooms is not limited. The natural process of decomposition of feces is accompanied by the release of gases harmful to households: methane and hydrogen sulfide.

If the system is equipped with a fan riser, at the moment of “throw-in” there are no such consequences, since the vacuum created in the collector simply does not have time to break through the hydraulic dampers in the siphons.

It is prevented by flows atmospheric air, which, simultaneously with the occurrence of a vacuum, are drawn into the system, blocking the penetration of gases into the room when draining and pumping out the septic tank.

Image gallery

When installing a fan pipe with a cross section of 110 mm, the check valve is connected using an adapter.

One of the ways to install a check valve in the cavity of the vent pipe and then connect it to the sewer outlets of the system

An important point: all operations for the installation of a fan pipe should be carried out on dry surfaces. At the stage of fixing the check valve, you should not use silicone sealants and any kind of lubricant.

Typical installation errors

Most often, the situation with the formation of a vacuum in the system occurs when pipes of different diameters are used in its arrangement. For example: the toilet is connected to a pipe D 110 mm, the bathtub is connected to a pipe D 50 mm, and the hole drain tank– D 70 mm.

Unpleasant stench in bathrooms often appears when plumbing fixtures are equipped with siphons that have insufficient volume. This arises due to the fact that with irregular use of devices in the siphons, the remaining water dries up, removing the damper and opening free access to the spread of "flavors".

By correctly calculating the dimensions of the fan pipe and installing it in compliance with all installation rules, you can almost completely eliminate the possibility of accumulation and the likelihood of sewer gases entering the house. And then there will definitely be no problems with the operation of the sewer system.

Do you have practical skills in installing a ventilation fan pipe? Share your knowledge or ask questions on the topic - the contact block is located below.