Installation of a sewer riser without ventilation. Sewer ventilation in a private house

Many copies were broken in disputes about how to properly make the exit of the sewer riser to the roof. The time has come to clarify this sewer issue, and the invaluable experience of our portal users will help us in this.

What is a vent pipe;
How it works;
How to do without it;
Is a diameter of 50 millimeters acceptable?
Ready solutions from FORUMHOUSE members.

Fan pipe: what is it?

How the fan pipe is arranged can be understood from this diagram.

In a sewer system, this is the element of the pipeline structure that is the connecting link between the septic tank and the atmosphere.

And it doesn’t matter whether you use it on your site or made it yourself.

It should be remembered that in most cases the installation of this sewer element is simply necessary, since when passing Wastewater a vacuum is created along the riser. The water in the siphons of your home's plumbing fixtures, under the influence of a vacuum, begins to be sucked into the sewer system, and this can lead to a sharp decrease in pressure, failure of the water seal and the appearance of an unpleasant odor in the premises.

A siphon or water trap is a curved tube located under the sink or behind the toilet and filled with water. The liquid, which is constantly located in the curved part of this device, plays the role of a water plug, preventing the penetration of unpleasant odors from.

OnFORUMHOUSEyou can get all the information you need about both near Moscow and in southern regions, and in permafrost conditions.

Fan sewer riser in a private house: the experience of FORUMHOUSE participants

Indicative personal experience our forum members. Let's look at one of the most asked questions.

Latysya Member of FORUMHOUSE

– I have a cesspool septic tank – concrete rings with bottom and lid. It is located 6 meters from the house. There are 3 windows facing this side. At first I thought of installing a ventilation riser outlet through the ceiling of the bathroom, then into the attic pocket and the roof of the house. I think this is necessary so that gases and other odors formed in the filling septic tank exit through it and dissipate higher above the roof. But the problem is that you don’t want to put holes in the roofing material. Help me understand whether there will be a smell from a septic tank without a ventilation riser, and what the diameter should be fan pipe in a private house.

Our forum consultant answers Evgeniy Fadeev :

Evgeny Fadeev:

– This sewerage element must be installed, and the pipe must have a diameter of 110 mm. If you don’t arrange it, then when the water seals dry out or break, a smell will appear. If there is no normal fan ventilation with inflow at the filter structure and exhaust at the roof, the smell will, one way or another, spread throughout the area. And for diameter you should remember a simple rule:

A 50 mm fan pipe will provide a flow approximately 16 times less than the flow through a 110 mm pipe. Thus, it will no longer be ventilation, but a set of several connecting tubes.

Sometimes homeowners come to the conclusion that the installation of this element of the sewer system is not necessary; they can do without it. But it’s easy to guess what will happen if you drain the water from the kitchen sink, bathtub and toilet at once, and there is no drain pipe in the design. But usually in modern country house two or more bathrooms are installed.

How do without a drain pipe in a private house

The answer to this question is: “in most cases there is no way around it.” It should be remembered that its installation is necessary:

When using sewer risers with a diameter of 50 mm in the communication system;
The house has two or more floors equipped with bathrooms;
or other equipment whose one-time flow can block the sewerage system.

Fan pipe on the roof: placement

Let's consider the following, very common situation: the house has already been built, the septic tank has been dug, the bathroom outlets have been planned, but the homeowner has not yet decided what to do next.

Prorab_2009 FORUMHOUSE Member:

– Help to properly arrange a fun exit to the roof. At the moment the situation is this: the house has been built, the roof is made of tiles, now it comes down to the sewer pipe, from the house to the septic tank 6 m. It is possible to break through the ceiling and install it under the roof tiles in a cold attic.

According to our forum consultant Vadim , in this case, the following scheme is possible, and method number 1 would be more correct.

Vadim

– The first method is the most preferable. Fungus on the riser is not needed. Rises up the pipe warm air, condensation may freeze on the fungus and block it, and do not conduct it under the eaves, in this case the draft will decrease. Don't put it in the attic - the draft is weak and the attic stinks.

Fan outlet to the roof - basic rules

User of our forum (forum nickname VladimirKu ) advises adhering to the following rules when removing the drain pipe:

It should go up to the roof, at least 300mm. And as close to the ridge as possible so that the snow doesn’t tear it off when it comes off the roof. And it is designed not only to protect hydraulic locks during internal sewerage your home, but also for ventilation of the sewer system.
If the house is more than 2 floors and has long horizontal internal wiring sewer system inside the house, then you will have to remove the second drain riser.
If you have an autonomous biotreatment system using microorganisms that require oxygen for their life, then a ventilation system is extremely necessary.

The risers are placed as straight as possible. Turns, bends and narrowing must be avoided so as not to create resistance to air flow.

In order for sewer ventilation in a private house to be properly designed, you should purchase high-quality plastic pipes, which is much more economical than iron analogues. Little weight and ergonomic shape allow you to develop various projects sewer networks. The plastic parts of the pipeline will not be affected by the aggressive gas environment.

Pipes for ventilation in a private house made of plastic will not be inferior to metal models, and will even serve more efficiently.

PVC has gained the greatest popularity due to its advantages:

they are light and have high degree strength;
ultraviolet rays have no effect;
easy to maintain;
do not cause harm to health.

To understand whether sewer pipes can be used for ventilation, you will first need to know all the nuances before purchasing materials. Air flow along the path ventilation pipes in a private house will entail the penetration of contaminated particles into the room. In another option, if the pipeline is planned to be installed in an exhaust system, all harmful particles will be drawn from the inside into the external environment.

It is best to make ventilation from the components of durable and expensive plastic, which will ensure the durability of the structure. Without unevenness, as with the accumulation of dirt in iron pipes, plastic options allow oxygen to circulate freely throughout the house.

Ventilation from sewer pipes It can be installed with your own hands using two options: forced and natural systems. Easiest to install natural system ventilation in the house, which consists of channels passing through the house and then rising to the roof. Forced sewer ventilation in a private house requires additional costs at the installation stage, namely the purchase of fans and valves.

Types of ventilation systems

There are two common ways to construct ventilation from sewer pipes:

internal hood;
external ventilation system.

At the stage of installing an internal sewerage exhaust system in a private house, all the nuances of the room and the laying scheme are thought out in advance. Important points:

The diameter of the fan (exhaust) pipe and the riser that extends it must completely match;

According to the rules, the height of the vent pipe must be at least 20 cm and a maximum value of 3 meters, especially if the roof has a steep slope. In most cases, the height of the pipe is a meter above the roof;
The sewer hood with pipe should be 3-4 meters away from the window or balcony;
They enhance the natural draft of the hood by installing a deflector.

Ventilation of sewerage in a private house according to this scheme is possible mainly at the design stage of the building, if it has not yet been built, otherwise they proceed to the external installation option.

External ventilation is installed in three ways:

Using a ventilation duct from a sewer pipe, which is mounted outside the structure. The difference from simple drainpipes is that the upper end of the ventilation duct is higher than usual, and its diameter is at least 11 cm;

Most a good option there will be an installation of a hood on a septic tank, which, located at a distance from the house, will relieve household members of unpleasant odors;

The sewer pipe hood can be located between the toilet and the septic tank.

How to arrange sewer ventilation

First, you need to decide whether ventilation will be needed for sewerage in a private house, and develop a detailed design scheme, which will depend on the number of floors and drainage points.

Ventilation in a private house from sewer pipes will prevent the penetration of a fetid odor into the structure, and if there are several risers, it is advisable to combine them into a common system.

Nuances of installing ventilation risers:

the exhaust pipe leading to the roof of the house must be extended at least a meter in height;
to avoid the formation of condensation and winter period ice jams on the top of the ventilation pipe, you should not install a cap there;
When combining several systems into one, it is important to buy pipes of the same diameter of 110 mm;
It is strictly not recommended to connect the general ventilation in the house and the sewer together;
To avoid damage from snow or ice in winter, do not place the vent pipe under the roof overhang.

To use vent pipes for their intended purpose, the following conditions must be met:

installation is possible in an apartment building if the drain point is above the first floor level;
the size of the risers does not exceed half a meter in diameter.

If the fan pipe for ventilation in a private house is not suitable, you can choose a simpler installation method using valves, but this may reduce the efficiency of the system. Owners should understand that ventilating sewer pipes using valves does not always guarantee the absence of unpleasant odors and noise.

How to make a ventilation valve with your own hands

To prevent sewer ventilation from becoming too costly, you can build a valve in your home yourself, which is simple in design and stable in operation. An experienced specialist always has at hand the materials with which to install a sewer ventilation valve. Despite the fact that valves are inferior to vent pipes, they prevent frost from forming in the pipeline by blocking the flow of warm air from the septic tank.

The sewer ventilation valve is manufactured in several steps:

First, you will need a small spring mechanism (a part from a ballpoint pen will do), under which you will select a self-tapping screw 45 mm long;
Next, a round plastic pancake with a diameter of 50 mm is made, and a hole is drilled in the center of the circle, suitable for inserting a self-tapping screw into it;
The spring in combination with the self-tapping screw must be inserted without any snags and rest against the pancake;
After this, a circle of larger diameter, approximately 60 mm, is cut out of cardboard, with a hole in the center where the self-tapping screw will be inserted;
Both products, a plastic pancake and a cardboard circle, are glued together;
A plastic tee 100 mm in diameter is prepared in advance, into which three small holes are drilled. All three holes should not be more than 4-5 mm. You need to check the distance from the holes to the edge of the cover; it should not be more than 20 mm.

The final action is to insert a self-tapping screw into the center of the cover, which will ensure the integrity of the entire structure.

How to check if the valve is working properly

The performance of the ventilation valve can be assessed after its complete assembly. Air is released from the lid hole, which should come out evenly. If, when you inhale air, it comes out, you need to compress the spring more and tighten the screw. Such actions will relieve the owners of the faulty valve and ensure its operation, so gases from the septic tank will not enter the air duct.

Valve Application

The most important thing when installing a ventilation valve is that it ensures tightness at low pressure in the sewer. This is useful for houses with three floors, three or four rooms. So that the incoming air contributes to equalization low pressure in the pipeline, it is worth choosing a diameter of the product larger than that of the horizontal drain. This will ensure reliable drainage of waste water.

The air valve must be designed for short-term operation in public places, have the necessary capacity and maintain constant pressure V common system ventilation.

With a constant air exchange of 33 to 48 liters per second, a comfortable microclimate is ensured in the house. An important indicator during installation air valve is its capacity, as well as compliance with regulatory requirements. Level bandwidth will depend on the number of floors of the room: the more floors, the correspondingly higher the indicator. Most often, to achieve ventilation, the throughput must be five times higher than the capacity of the riser.

Important! For ductwork to function properly, it must meet industry regulations and standards. At the design stage of a building or when changing the arrangement of an already created room, the indicator of the ejection capacity of water, that is, the suction capacity, must be taken into account.

To prevent the appearance of foul odor from the sewer, use ventilation system from fan pipes or valves. These devices will not require a lengthy installation process, but will thus be effective in the overall design of the sewer system. Their installation must be carried out at the design stage of a private house.

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In order for a private home to have all the conditions for comfortable living, it is necessary to install a sewage disposal system. Plumbing fixtures are drained using a vacuum, which pulls recycled water out of siphons. This may release stench into the surrounding area. Ventilation of the sewerage system will help avoid this.

Ventilation of the waste system will ensure:

removal of stench from highways, preventing them from entering residential premises;
stabilization of pressure in pipes;
suppression of noise in the system that occurs when wastewater is discharged.

Organization of ventilation of the sewer system

To lay a drainage system in a private house, permits are not required, so its design is often carried out in violation of the standards. This causes a disruption in the functioning of the sewer system. Adherence to construction, as well as sanitary standards and rules developed for residential buildings will help to avoid system failures.

The need to ventilate external treatment facilities

For effective air exchange sewer system, it is necessary to comply with the rules for its installation:

if the diameter of the central riser exceeds 50 mm, or the plumbing fixtures are located on different floors of the house, it will be necessary to install a fan main - an ending leading outside the building through the roof. It prevents air rarefaction in the waste system, preventing the release of stench into the living areas of the house;
The size of the hole in the fan main must match the cross-section of the riser.

Note: there are no standards regulating the ventilation of the external sewer system of a mansion, but experts recommend arranging air exchange for external cleaning facilities to avoid stagnation.

Stages of organizing air exchange in the sewer system

Based on current standards, we can identify the main stages of organizing sewer ventilation in a cottage:

ventilation of the riser, including installation of a vent pipe;
organization of air exchange in the external sewage system (septic tanks, sewer pits, VOCs).

Pipe selection

They are used to ventilate sewers. Their advantages:

ease;
ease of installation;
complete set with rotating, connecting elements, fasteners.

The diameter of the pipes for sewer ventilation depends on the area and complexity of the house structure. For one-story buildings, communications with a hole of 50 mm are sufficient, for multi-story buildings - from 110 mm.

Rules for arranging a ventilation riser

Each plumbing element is equipped with a siphon, a curved tube constantly filled with water. It is a kind of water seal that prevents wastewater and unpleasant odors from entering the living space. But when there is a strong drain in the sewer, a vacuum occurs, sucking water out of the siphon, which causes stench to spread throughout the house. This situation often arises in a multi-storey cottage with several bathrooms, with simultaneous drainage from different floors.

To avoid this, the ventilation pipe is removed from the house through. The communication must be 4 m above ground level - then there will be no problems when draining. airlock, the water will remain in the water seals, and bad smell will be output by the system. For this pipe, even at the design stage of the house, a special shaft is provided.

Tip: if the installation of a (ventilation) pipe for the sewerage system was not included in the cottage design, it can be laid along the vertical plane of the wall, covered from the outside with a plasterboard niche or a decorative box.

Ventilation risers in a mansion are arranged according to the following rules:

the fan main must be at least 30 cm higher than the roof. Minimum distance from the air outlet main to the nearest windows and balconies - 4 m. If the attic in the house is used, the end of the riser is brought to a level of 3 m above the roof. This will ensure that the wind removes unpleasant odors. It is not recommended to install the vent pipe under the roof overhang - ice and snow coming off the roof can damage the structure;
a cap/deflector is not installed at the outlet of the air duct; this may cause condensation to form and freeze in the winter;
the joining of several ventilation systems is carried out using pipes of the same diameter (usually 50, 100 mm);
The air outlet from the sewer is prohibited from being combined with a chimney or room ventilation system.

Please note: following these rules will protect your home from stench from the sewer.

Installation of a drain pipe

The efficiency of removing recycled air from your home largely depends on proper arrangement fan pipe. In modern siphons installed on plumbing fixtures, the water supply is small. If the device is not used for several days, it dries out, allowing air from the sewer into the house.

A fan pipe will eliminate this defect. Through it, the warm exhaust air is discharged outside, causing a vacuum inside the system. A pressure difference occurs due to which the air from living rooms is sucked into the sewer system. The pressure drop inside the lines disappears, and unpleasant odors do not enter the house.

Structurally, the drain pipe is an extension of the riser, so it must be made from a similar section of pipe. To create traction in the communication, its lower exit is arranged in a warm room, and the upper one in a cold room. To allow the vent pipe to exit into the attic, a special sleeve is formed in the ceiling of the house. The gaps between the edges of the hole and the line are sealed. The pipe exit to the roof can be vertical or at an angle.

If there are several risers in the house, they can be connected to attic space a single fan pipe. For this, plastic 45˚ elbows or tees are used.

Installation of Vacuum Valves

If for some reason it is impossible to bring the drain pipe to the roof of the house (due to the specific design of the building, the complexity of the sewer lines, weather conditions), it is replaced ventilation valves. They are designed to regulate the pressure inside the system.

One is installed on the upper outlet of the sewer riser. It has a low-resistance spring and a sealed rubber seal. When a vacuum occurs in the air in the system, the valve opens, allowing air into the sewer. After the pressure in the sewer lines has stabilized, the diaphragm closes, preventing stench from escaping from the riser into the living areas of the house.

In addition to the riser, ventilation valves are installed in horizontal sections of the pipeline. Their number and location are determined by the number of connected plumbing fixtures and the length of the highways.

Please note: vacuum valves are not a complete replacement for a drain pipe - they are additional elements sewer ventilation systems. Over time, they become clogged, worn out and require replacement.

Sewer ventilation repair

The presence of problems with air exchange in the waste system is indicated by the appearance of unpleasant odors in the house. The reason for this may be:

incorrect installation, or failure of the siphon of one of the plumbing fixtures. Eliminates by reinstalling or replacing this element;
malfunction of the water seal. The reason for this may be the use of small-diameter sewer lines or clogging;
leakage in the riser;
clogging of ventilation ducts.

Sewer ventilation is a necessary measure in a private home. The organization of this system will prevent exhaust gases, unpleasant odors, and fumes from entering living quarters and will ensure the comfort of all inhabitants of the cottage.

The absence of a drain pipe and other devices will sooner or later lead to the fact that the sewer ventilation will be disrupted and the unpleasant odor will quickly spread throughout all rooms of the house. Regardless of the presence of a centralized or autonomous system, ventilation problems must be solved as quickly as possible. But if a visiting master successfully copes with this in an apartment, worries about a private house fall on the shoulders of the owner. And it’s worth talking in more detail about how to arrange ventilation for a private house or fix problems with your own hands.

The presence in the house of risers with a cross-section of more than 50 mm, two or more floors and a large number of plumbing fixtures dictates the need to install a ventilation system. A sharp burst discharge of a large volume of water creates a vacuum in the pipes, as a result of which the siphons are emptied. And it is the absence of a water seal that allows odors to freely penetrate the room.

Even if the house is equipped with large pipes and there is minimal risk of blocking the cross-section with the drain flow, air from the sewer can still appear in the room. The reason is the small size of the siphons. If the sewer is not used for 3-5 days, the water dries out and a void forms, the water seal valve does not work again and the aromas spread into the house. Troubles can be avoided if there is sewer ventilation in a private house, which is quite easy to do with your own hands. The system may consist of a regular drain pipe or use a vacuum valve. Both options are good, they are used not only in private houses, but also in apartments, and the most effective is considered to be a scheme where there is both a drain pipe and a valve, which plays the role of a necessary addition.

Sewerage with drain pipe

The device is a continuation of the sewer riser, which is discharged outside. The principle of operation is simple: warm air always rises upward and is discharged outside, as a result of which a small type of vacuum is created in the pipe system (like draft in a stove) and the air is pushed out of the rooms of the house into the sewer, and not vice versa.

Important! The drainage pipe is carried out through a special shaft, provided at the stage of laying the house. But if it didn’t work out to make the device, then you can route the pipe system horizontally through the wall on the side.

But in order to properly arrange a ventilation riser with a waste pipe with your own hands, take note of the following recommendations:

The height of the vent pipe cannot be less than 0.5 m from the roof level. If there is an attic, the length increases to 3-3.5 meters;
The cross-section of the hood diameter must be equal to the diameter of the riser pipeline;
If there are many sewer risers, it is allowed to connect the elements in the upper part and equip the system with one drain pipe;
Ventilation cannot be connected sewer type with stove or general house exhaust ventilation;
The best place for pipes is a blank wall of a house. If displayed next to window openings or balcony, the smell may seep into the house. If there is no blank wall, the distance between the windows and the outlet of the sewerage pipeline must be at least 4 meters;
If the roof of the house is multi-sloped, the vent pipe should not be placed under the overhang of the slope; the structure can easily break due to snow melting;
Equipping the top of the hood with a deflector is guaranteed to block the ventilation in winter. Condensation forms on the deflector, which, when frozen, will tightly block the outlet and the air will flow into the rooms.

The hood is made from a pipe from which a common riser is made and is a continuation of the pipeline, leading it outside. The use of cast iron is not advisable, since the material is susceptible to corrosion and there is a risk of complete rusting and falling of the pipe; it is best to make the outlet plastic.

Advice! The fan pipe needs to be insulated. Of course, everything depends on the region and temperature changes. However, even with mild winter frosts, insulation will not interfere with summer cottages, where sewerage is used only in the warm season.

Sewerage installation with a vacuum valve

The use of a valve is necessary if it is impossible to install a drain pipe. The system works like this:

inside the case there is a spring and a rubber seal;
when a vacuum forms inside the riser (volley discharge of a large volume of water), the spring opens the seal and air passes into the system, equalizing the required pressure;
after which the spring returns to its place, as a result of which air from the sewer does not enter the rooms.

A vacuum valve cannot serve as an equivalent replacement for a drain pipe, but it does its job well; however, when the water in the siphon dries out, the valve will not prevent the spread of unpleasant odors.

Important! The vacuum valve is always mounted at the top of the riser and only in a heated room.

If it is impossible to install the element on a riser, installation is carried out on a pipe running horizontally. Installation rules:

the element is mounted above the point of connection of the pipes to the sewerage system of the highest drain of the plumbing fixture;
if the drain is at floor level, the valve is installed at a distance of 35 cm from the height of the floor covering;
It is necessary to ensure free air intake into the vacuum device, as well as access for repairs and manual opening (if necessary).

External ventilation: system arrangement

When equipping a home autonomous system sewerage, ventilation can be used external type. There can be two location options:

hood outlet along wall panels Houses. In practice, this looks like a drain with the end of the pipe above the roof level. The scheme involves removing the structure from the house and attaching it to the wall element using clamps;
installation of pipes on a septic tank - convenient option, since the pipe is located away from the house and completely minimizes the possibility of odor entering the rooms.

External sewer ventilation in a private house is equipped in the absence of a sewer riser, which happens in small buildings or seasonal houses. Usage this method involves installing a vacuum valve to improve the ventilation system.

Cesspool ventilation: purpose and types

Ventilation pipes are necessary not only to prevent odors from appearing in the house, but also to balance the pressure within the entire system. However, there is another reason for the mandatory arrangement of ventilation: during the decomposition of organic waste, flammable gas and with a large accumulation of the substance, a fire is possible. To prevent this from happening, ventilation is necessary. cesspool. The device will not require large expenses, and you can make it yourself.

The hood circuit can be equipped extremely simply:

install normal sewer PVC pipe with a cross section of 100 mm;
attach the pipe to the wall at the back;
bring the upper end beyond the roof of the septic tank to a height of approximately 20 cm;
insulate the pipe from below with tow soaked in bitumen;
cover the exit from debris with a sheet of tin;
concrete the exit pit.

Advice! To generate powerful traction, the top of the pipe is equipped with a deflector.

If ventilation is installed for a cesspool without a toilet, installation also does not take much time:

install a pipe system next to the hatch, the size of which is calculated by the depth of immersion and the height of the outlet;
equip the top of the outlet with a motor to enhance traction;
cover the exit with a tin sheet.

The sewer hood is ready, and thanks to the presence of a motor, there will be no stench in the area even on the hottest summer days. In addition, there will be no unpleasant odors in the toilet, decomposition vapors will no longer affect the wood, which means the toilet will last longer.

When building a toilet with a drainage pit, it is better to build the toilet away from the pit. It is easy to connect the structures using a conventional sewer pipeline with a cross-section of 100 mm or more. And if you mount a tee, it will be easy to connect the ventilation pipe, which guarantees good ventilation. In any case, ventilation is possible in two ways:

the natural option occurs when the pressure in the drainage pit increases;
forced - air moves through the operation of fans connected to the power supply.

Natural ventilation

Installed vertical pipe, which is needed to remove odors, and the installation is carried out no lower than the level of filling the pit with sewage, and the top extends beyond the roof.

The cross-section of the outlet must be more than 100 mm, the upper end must be at least 70 cm from the roof level. Sealing the pipe and securing it with clamps is mandatory - this way you don’t have to worry about the pipe being blown away during a strong wind.

Forced ventilation

Most effective method, but requiring electricity. It’s easy to make a hood with your own hands:

connect electricity to the toilet;
choose a medium-power fan (300 watts is enough);
form a hole for the device, and the fan should work for expulsion so that the air does not stagnate in the toilet room;
equip several openings for the flow of fresh air (this can be a regular gap at the threshold).

In this case, the scheme does not provide for the installation of ventilation pipes in the drain pit itself; a fan is sufficient, which will perfectly expel the air and along with it all the unpleasant odors.

Well, to avoid the appearance of a strong odor in the drainage pit, it is enough to purchase biological cleaning products. These can be powders, tablets or liquids for sewer pits. As you can see, the ventilation device is quite accessible to any owner, and the choice of systems is quite diverse.

A drain riser is a pipe that connects the sewerage system to the environment, i.e. atmosphere. In practice, this looks like a continuation of the sewer riser, which is discharged through the attic to the roof.

Therefore, the fan riser is also called a ventilation riser. But why does the sewer system need ventilation? Many beginners mistakenly believe that it only removes unpleasant odors from the sewer, but this is far from the case.

To answer the question posed, let's look at what processes occur in the sewer system when a large amount of waste flows through the riser.

In this case, the pipeline works like a pump, in which wastewater flowing in a large volume serves as a piston. Accordingly, as they move down in the sewer system, a zone of rarefied pressure appears above the drains. As a rule, this happens after flushing the toilet.

If the discharged pressure is not normalized by drawing in air through ventilation, air is sucked in through plumbing fixtures. As a result, the water seal breaks down in the area where it is weakest. Those. the water in the water seal is simply sucked into the system.

Let us remind you that a water seal is, in fact, a water valve that prevents the penetration of unpleasant odors from the sewer into the room. It is formed in a siphon, which must be installed between each plumbing fixture and the sewer.

Therefore, in the process of breaking the water seal, a characteristic “gurgling” sound is heard from the plumbing fixture, which is probably familiar to many apartment owners in multi-storey buildings. After this, an unpleasant odor appears in the room, as gases from the pipeline begin to escape freely.

As you probably already guessed, a ventilation riser is precisely what is needed to equalize the pressure in the sewer system. According to current SNiP, it must be installed in all houses that have more than one floor.

Keep in mind that the lack of ventilation leads not only to the failure of water seals, but also to a deterioration in the permeability of the pipeline. This is especially noticeable in the “lying” section.

Accordingly, there can be no talk of any dismantling of the fan pipe, since this will only lead to a number of problems.

Ventilation rules

To sewer ventilation worked effectively, it must be carried out in compliance with the following rules:

Air valve

There are situations when the drain pipe is not enough for the normal operation of the sewerage system, i.e. the water seal breaks, despite its presence. This may occur due to a clogged system or improper installation. In a private house, sewer ventilation may be completely absent.

What to do in such cases? Of course, you can resort to extreme measures - replace old design or install a new one from scratch. However, there is a simpler solution - installing an air valve.

The principle of this device is extremely simple - it allows the system to freely suck in air from environment, but immediately blocks the exit in the event of reverse draft. Therefore, gases from the sewer cannot escape through the valve.

It must be said that the air valve is a rather capricious device. Therefore, for its correct operation, it is necessary to follow certain installation rules:

Keep in mind that the capacity of the air valve is significantly less than the capacity of the fan ventilation. Therefore, it cannot be considered as an alternative to a riser in multi-storey buildings.

That, in fact, is all the information regarding sewer ventilation.

Conclusion

As you can see, without fan boner it is impossible to ensure the normal operation of most internal sewer systems. Therefore, if this element is present in your sewer system, then under no circumstances should you get rid of it. The exception is private homes, where an air valve can be used as an alternative.