Non-return sewer valve: principle of operation and installation

The principle of operation of ventilation in the sewer system

Drain outlets of plumbing fixtures are connected to the general sewer system. Wastewater is discharged spontaneously into a riser, which is a vertically located pipe, the diameter of which is most often 110 mm. It passes through several apartments, at the bottom it opens into a collector. From the reservoir, wastewater enters a centralized system.

The top hole is located above the roof level. The plug is not installed here. The ventilation hole allows air to pass through, which is needed to maintain the required pressure in the public sewer system.

This system is called a fan pipe. It is installed in all multi-storey buildings. Sometimes it is impossible to arrange such a structure. If the vent is located a short distance from the windows, the apartments will smell like sewage.

How to get rid of amber penetration

In this article, we will consider in detail the issue of choosing and installing a vacuum valve on our own.

You can solve the problem by installing a drain pipe (what is it).

In this case, the following rule must be observed:

The cross-section of fan hollow objects must be no less than the diameter of the sewer pipes.

You can protect your living space from flooding with sewage and the spread of disgusting stench by installing a vent valve (at what distance from the house to install a septic tank is indicated here).

Under these circumstances, when the water in the siphon dries up, the air in all rooms of the house always remains clean and fresh.

As mentioned above, fan pipes do an excellent job of this task.

But in order to install them, you need to have certain knowledge and skills.

What is also important is that the pipe must be routed only through the roof, and this violates its tightness.

Among other things, it is not recommended to install vent pipes indoors.

Do you know about the Termit septic tank? The manufacturer’s official website claims that the equipment they produce is cheaper than that of its competitors. Read owner reviews in this helpful article.
For what reason there is a need to buy a Kozlov compensator for polypropylene pipes, it is written on this page.

Important point ! The sewer pipe must be equipped with a ventilation system that will function flawlessly.

Remember , no residential premises are insured against all kinds of emergency situations.

This also applies to clogged sewer pipes. In this case, wastewater will flow from the toilet (which sewer pump with a grinder to choose, read this article) into the living areas of the house.

Most often, this problem occurs on the first floors of a building. Many people have encountered this unpleasant situation; at best, they have heard about it.

Why do you need a valve for a sewer riser?

The vacuum sewer valve is mounted at the top of the riser and near plumbing fixtures.
The sewer system may not function properly for the following reasons:

Failure to comply with rules and regulations. If the installation of the fan structure is carried out incorrectly, an unpleasant odor penetrates into the premises.
Violation of the integrity of the riser.
Clogged top of pipe. Leaves, particles of building materials, birds and animals can get into the hole.
Freezing of the outlet of the fan structure. In this case, the air flows in insufficient quantities.
Lack of ventilation structure.

When water is drained, a vacuum occurs in the collector. If the pressure drops, the siphon seals disappear. As a result, an unpleasant odor and noise appear in the room. Sewage gases pose a danger to humans. If the problem is not eliminated, fungus begins to spread in the bathroom and toilet rooms. Installing an aeration valve on the drain pipe helps to avoid this. The part promotes the regular flow of air, equalizing the pressure. It can be used in combination with a fan system.

Does installing a vacuum valve solve all problems?

Alas, no, of course not.

Let's return again to the fan pipe, made according to all the rules. It not only performs the function of equalizing pressure inside the system, but also provides effective ventilation. Its installation is highly recommended in the following cases?

If the house has more than two levels (floors) with installed plumbing and sewerage running through all these levels.
If for some reason you had to install a riser from a 50 mm pipe.
If the house has a large tank, something like a sauna pool, which has to be emptied periodically.
If the septic tank is located close to the house, and an unpleasant odor emanates from it into the living area.

That is, in such situations, the need for a vent pipe, in theory, should not even be discussed.

Sometimes homeowners are tempted to not bother with running pipes through the roof. That is, limit yourself to installing a vacuum valve at the top point. I must say right away - this is not the best option.

The aerator should be considered as a necessary measure when removing the drain pipe is impossible in principle. Or - to simplify and reduce the cost of a general scheme with several risers. There is no need to bring them all out through the roof to the street - one drain pipe will be enough, and on the remaining risers, high-quality valves at the highest point in the premises are quite sufficient. That is, ventilation will be provided - and the issue will also be resolved with vacuum.

Here is one acceptable solution to the problem: several risers, of which one goes into a waste pipe, and the rest are equipped with vacuum valves at their highest point.

Is sewer pipe ventilation really that important?

Firstly, when organic matter decomposes, gases that are extremely dangerous to human health are released. And poisoning with such products, including fatal ones, is not at all such a rarity. It is better that they do not concentrate, but release into the atmosphere in a timely manner.
Secondly, there is another pitfall. If there is no ventilation air circulation in the pipes, then the accumulation of fetid gases has nowhere to go, and sooner or later it will leak into the premises. A simple example: a family, having been out of town for the weekend, went to “winter quarters” for a week. During this time, water simply dried up (evaporated) from some very small siphon (say, a drain in a shower room or a siphon under a bathtub). And the beloved dacha greets its owners with a wild stench in the rooms, as gases accumulated in high concentrations from the sewer rush out.

And with a drain pipe, such large-scale troubles can be avoided.

* * * * * * *

Conclusion: a vacuum valve is a very useful element of the sewerage system, which in some cases allows you to significantly simplify the circuit and avoid breakdowns of water valves on long horizontal and other problem areas. But considering it as a full-fledged replacement for a waste pipe is unacceptable!

The reason is that it does not provide the necessary ventilation of the sewer line. Without this, talking about the usefulness of the system being created will still be an exaggeration.

Design and principle of operation of the fan valve

The ventilation valve consists of the following components.

Frame. There is a channel in the side through which air flows penetrate. The body is made of polypropylene or polyvinyl chloride.
Lid. The removable element allows the valve to be cleaned.
Membrane. Made from rubber.
Sealing gasket. Determines the amplitude of movement of the rod and imparts tightness to the structure.

On the left - the valve is open, on the right - the valve is closed.
The device works like this:

When the pressure in the pipe is equal to atmospheric pressure, no air enters from outside.
When you drain a toilet tank, bathtub, or other appliance, a vacuum occurs in the riser. The rod moves, causing air currents to flow.
The pressure in the sewer system is equalized. The rod returns to its previous position, the air flow stops.

Additional Information

The failure of siphons in small country houses can be eliminated without the use of air valves. But by no means can the valve for ventilation of the sewer system work.

It's hard to say why, but some installers love vent valves. They literally put them where they are needed and where they are not needed. Either because installing an additional valve may cause an increase in the cost of work, or for some reason of their own, known only to them.

Important: STO NOSTROY 2.17.176-2015 directly prohibits the replacement of a hood with a valve, provided that the building has a sewer outlet into an autonomous cleaning system.

Some people use the valve as an additional means of preventing small traps in bathtubs or showers from falling off. This approach is justified, but precisely as a means of additional protection. But under no circumstances should you trust the ventilation valve to perform the ventilation function. It's not designed for that.

I hope that my article will allow you to avoid difficult mistakes when arranging sewer systems and that you will forever remember that the ventilation valve cannot replace the drain pipe and is not intended for this.

Pros and cons of aerators

The positive qualities of the aerator include:

Normalization of sewerage work. Installing an auxiliary part prevents the spread of an unpleasant “aroma” that is dangerous to the human respiratory system.
Possibility of refusing to install a drain pipe. The placement of the aerator allows you to avoid creating an exit in the roof of a private house.
Possibility of installation in a non-ventilated riser. In this case, the valve only works effectively in a low-rise building. In multi-storey buildings, the part is used in combination with a fan structure.

The disadvantages include the possibility of the rod jamming. This is caused by membrane wear or clogging of the aerator. The second is unlikely; debris gets into the case only when the lid is opened.

Installation

For the most part, plastic sewers are installed in private houses and apartments. Air valves are also selected from the same material - PVC or polypropylene. Like any sewerage products, they have a socket with a rubber seal at the end. The whole installation consists of putting the device on the prepared pipe. All.

For reliability, you can first coat the joint with plumbing sealant, but even without this measure the connection is airtight (as long as the pipe and device are of normal quality).

Technical characteristics, diameters and manufacturers

Important technical parameters of the device are:

Diameter. Selected according to pipe dimensions. The diameter can be 5, 7.5 or 11 cm. The first 2 types are installed on intra-apartment systems, the last - on the riser. Some valves can be placed on sewer elements of different sizes. This becomes possible thanks to the introduction of a stepped pipe. On pipes of non-standard sizes, tees with a ventilation valve are installed.
Bandwidth. This parameter reflects the volume of air entering per second. For 1 l/s of wastewater, up to 25 l/s of gas is required. The valve capacity can reach 37 l/s.

In our country you can purchase vacuum valves manufactured by HL (Austria), McAlpine (Great Britain), Wavin (Poland), Europlast (Ukraine), Ostendorf (Germany).

Criterias of choice

There is no difference in quality of operation between imported and domestic valves. The only difference is in the quality of the surface of the material (there may be burrs that can be easily removed with a knife); these shortcomings can be ignored.

Advice! When purchasing equipment, you should not take into account the country of manufacture and brand; cheap valves will work no worse than expensive ones.

When choosing a suitable valve, you need to take into account the features of the sewer system. The type, dimensions and number of required vacuum valves directly depend on its diameter, length, slopes, and the number of installed devices.

When choosing, take into account:

Device Features . Different models have a stem or diaphragm;
Installation location . Take into account whether the valve is to be installed indoors or outdoors. Possibility of ingress of dirt and foreign objects, hidden or open installation, possibility of environmental influence;
Quality and cost of the device . Products from Germany and Russia have a good reputation. But with equal quality, devices made in our country are 3 times cheaper.

Attention! Experts say that valves with a stem are easier to use and maintain, and last longer.

Where and how to install the valve correctly?

The vacuum valve must be installed in a free place - this will provide access to the device for inspections.
When placing the valve, the following rules must be observed:

If the aerator is installed in the attic, the temperature should not be allowed to drop to sub-zero levels. This may disrupt the system.
In a shower room with a drain on the floor, the device is installed at a height of at least 35 cm from the surface.
You must maintain access to the device. This allows inspection and repairs to be carried out. Particular attention is paid to this point in the absence of a fan structure.
The valve is placed 30 cm above the topmost outlet. Other pipes are not placed within the specified radius.
The distance from the siphon to the aerator should be more than 20 cm.

Possible locations for installing the device

There are 3 suitable places for installing the device:

Riser. The aerator is located at the top of the pipe, leading into the attic or leaving it in the toilet room.
Near the outlet of the drain hose of a plumbing fixture. The device is often installed when installing a washing machine or dishwasher.
Long sewer elements located vertically.

Do-it-yourself valve installation - in apartments; in a private house

You can install this element yourself or call a specialist. There are no differences in installation in a private house or apartment; the same installation principle is present everywhere. But when performing installation, the following rules must be observed:

The device must not be installed in rooms where heating is not provided.
When using the device, it is important to provide free access to it for inspection or preventive inspections.
When installing the automatic version, it is important to find out the point of the highest flow into the riser.
Fixation is made above 10 cm from this point. This is true if a drain has not been installed.
If the ladder is equipped, the part is attached 35 cm above the level of the floor covering.
The valve should be placed in the socket in the area with the O-ring. The vertical direction will ensure good functionality of the sewer system.

Modern appliances can be used in the bathroom or toilet.
They are easily installed on the riser. Simple devices are placed on the washbasin, bathtub or sink. For the fan pipe, it is recommended to choose a cylindrical design. The 50mm diameter sewer air valve dilutes the system air in horizontal areas. It must be installed on long sections of the pipeline. When creating a slope, a natural outlet of the drainage system will occur.

Air valve for sewerage with a diameter of 110 mm, mainly used on drainage pipes. Under certain conditions, mounting to an auxiliary riser is permissible. The mechanism must not be mounted at an angle.

The valve must be installed following the exact instructions. It can be mounted into a flange, threaded or using a coupling. You should create airtight connections and joints, and then check this parameter after completion of work.

At the beginning of installation work, be sure to check whether the water supply taps are turned off. Then the required pipe element is dismantled and a valve is installed on this section. If the pipeline is placed horizontally, you need to check the direction of water flow with the parameters on the device. It is not recommended to rearrange the socket and inlet pipe, as the valve will not start.

The mechanism is installed into the socket of a plastic pipe without auxiliary parts, and the tightness is ensured by a special seal from the socket. When installing in a cast iron pipe, you will have to use an adapter. This option has a more complex installation.

During installation work, it is necessary to ensure a tight connection between the main device and the elements of the comb and socket.

If the structure has a bell-type connection, installation work is performed as follows:

Surfaces are cleaned of dust.
The seal ring is cleaned and degreased, then a trench is laid.
Contacting parts are lubricated with sealants or glycerin, which reduces friction.
The end of the valve is brought into the socket to a special mark.
At this stage, it is important to check the quality of the fastening by turning it.
Additionally, the area with the fixed valve is secured with a clamp.

After completion of the work, the joints should be inspected for leaks.

Watch the video

McAlpine Sewer Vent Air Valves

Prices and manufacturers

Models are selected taking into account certain criteria. This is a diameter, the value of which can be 50, 75 and 110. As well as throughput - the figure varies between 7-37 liters per second.

Products from the following countries are represented on the Russian market:

The HL company from Austria offers the most expensive designs. The price varies between 2500-3600 depending on the models.

McAlpine from the UK provides products in the average price category of 1200-1300 rubles.

You can also purchase inexpensive air valves from domestic manufacturers Sinicon and Politek. The cost of devices varies between 150-380 rubles.

Types of valves

There are different types of these devices. They differ in the features of their work. Let's look at them.

Automatic - in demand for use in small private households. The device will not cope with significant loads.
The kinetic valve functions correctly at low pressure. This device protects against air accumulation during drains.
A combined option is a device that combines two types.

The pipeline can be installed in any direction. And for each case there is a separate option. When installing an air valve on a sewer, the diameter of the pipes must be selected correctly.

Watch the video

This factor influences the division:

The receiving aerator has a diameter of 20 cm. The device is equipped with a filter that retains solid suspensions. This option is mounted on a horizontal highway.
Ball devices are fixed to pipes with a small diameter. The device uses a ball part as a shutter.
Inter-flange devices are characterized by compactness and low weight. Products are available as walk-through or corner. The shutter is represented by a special plate.

It is worth classifying products according to the method of fastening. The devices can be installed by welding. This option is not suitable for residential premises. For pipes with a small diameter, fasteners with couplings are suitable.

If the valve does not have a fastening element, it is clamped between the flanges. Fixation through flanges using a seal is also often used.

Features of operation

The nuances of installing a sewerage device are regulated by special SNiP standards. In order for the device to serve for a long time, it is necessary to monitor its serviceability and regularly check the quality of operation.

Problems can be caused by the rod or membrane sticking in one place.
If the device is jammed open, sewer odors may enter the room.
When stopped in a closed state, the water seals may fly off.

The special strength of the design and systematic testing of the device will allow you to avoid emergency situations.

Installing the device in combination with fan or ventilation outlets helps to avoid failure of water seals.

If the device has ceased to cope with its duties, then the reason may be a malfunction of the sewer system as a whole. In this case, you need to pay attention to whether household appliances were recently installed - a washing machine or dishwasher.

Watch the video

Eliminate sewer odor

When draining under pressure of water into the sewer system, the functioning of the system may be disrupted. In such a situation, it is recommended to install an additional device that ensures the operation of household appliances.

Principles of sewer system ventilation

The riser output channel is vital for the system so that all devices connected to it work properly.
It is much easier to explain the need for a good ventilation system if we consider the basic principles of its operation:

Discharged water from plumbing fixtures enters the riser.
Once in the riser, the water begins to draw in air, creating a vacuum or negative pressure difference. This is especially important when draining large volumes of water, since in this case there will not be enough air in the system to stabilize the pressure. The magnitude of the rarefaction will be so great that its value can safely be called critical.
The appearance of negative pressure causes water to enter the pipe from the weakest water seal. This process is called breaking the water seal, because in order to equalize the pressures, air must appear in the system - but there is nowhere for it to come from. The only place is the sink, since the resistance in these areas is always less. As a result, air is drawn into the system from the siphon, thereby destroying the water barrier.
Then everything is clear: the water sucked out of the siphon valve allows sewer odors to enter the living space. Of course, they take this opportunity and enter the house, thereby disturbing the peace of the residents. Given the fact that some sewer gases can be toxic or explosive, it becomes clear that their occurrence must be avoided.

Types of aerators

There are mechanical, electric and petrol tools. How to choose an aerator? Most gardeners are guided by the surface area of their lawn. If hand tools are suitable for small areas, then it is more advisable to aerate a large lawn using electric or gasoline machines.

Aerators for small areas (manual, foot, mechanical)

metal forks
studded sandals
rake
mechanical roller with spikes

Pitchfork. Using an ordinary garden fork, you can aerate a small lawn. The lawn should be pierced approximately half the depth of the tool. A puncture of 7–13 cm will be most optimal. It is not recommended to make frequent holes; 10–15 cm between rows will be enough.

Sandals with spikes are suitable for aerating a small lawn. The plastic or metal sole is secured to the shoe using several straps. The sole of the foot lawn aerator is equipped with 15 - 20 spikes, 3-5 cm in length. It is necessary to carefully secure the sandals to your shoes and walk in them on the grass. Steps should not be taken infrequently, approximately 20–30 cm each. To make walking easier, it is recommended to raise the sole of the foot parallel to the ground. A good exercise to improve your health!

A rake can also be used for aeration. It is inconvenient to make punctures with them, but by scraping along the surface of the earth, it loosens, which helps to aerate the soil. They are made from high-strength steels and equipped with thin, long teeth. A rake allows you to remove dry leaves, grass clippings and weed roots. Use the rake only on short-cut grass!

A mechanical aerator is a heavy iron roller with sharp spikes attached to its surface. Under the influence of the weight of the roller, the spikes penetrate the soil, loosening it. The disadvantage of a mechanical lawn aerator is that its use requires physical strength and considerable dexterity.

Aerators for treating large areas (electric and petrol)

These tools are quite expensive, so you should choose them responsibly

When choosing a tool, you should pay attention to the following features:

Engine power. If the lawn area is large, then choose an aerator with high engine power. Such machines have an increased engine life, which allows the engine to operate longer than usual.
Width of working surface. The wider the working surface of the aerator, the larger the area it can process in one pass.
Machine body. Plastic is lightweight, but metal is much more durable.
Container for collecting grass. It will be needed if the lawn area is large.
Types of knives. Aerators have long metal spokes that pierce the soil cover. Scarifiers have special knives that remove withered grass and weeds.

For large areas of lawn, it is recommended to use electric or gasoline lawn aerators. Some models are multifunctional and equipped with additional sets of attachments, so scarification and aeration are available to them. Such universal machines perform several functions:

make punctures (aeration) or cuts (scarification) in the soil
remove caked grass residues
collect the removed grass stems into a special container
loosen the soil using an additional attachment.

An electric aerator is convenient if the length of the cord allows you to treat the entire lawn area.

Electric aerator/scarifier

The gasoline device can be effectively used over a large area because it operates autonomously.

Gasoline aerator

Device

The operating principle of a vacuum sewer valve is extremely simple.

Valve operating principle.

If there is excess pressure in the riser, the valve is pressed tightly to the seat and does not allow air to pass through, preventing the attic or apartment from being saturated with waste aromas;

At zero pressure difference it is also closed. The bolt is held in the seat by its own weight.

As soon as a vacuum develops under the valve, the valve will be raised by the pressure difference and open the way for air into the riser.

Disassembled valve. Below in the photo is his shutter.

The valve design imposes a couple of restrictions on its use:

It can only be installed in heated rooms. A drop in temperature below zero will cause vapors to freeze on the valve seat and on the valve itself. The consequences are not difficult to predict;
The valve requires periodic cleaning. Dust settling on the seat will deteriorate its seal over time. If there is a noticeable smell of sewage in the bathroom, the first thing to do is open the valve and wash the seat and the valve itself.