The air check valve is plastic. Extractor hood for a bathroom in a private house: types, non-return valve, installation and installation

Someone may consider this detail superfluous, they say, it makes it difficult for the already weak outflow of air from the room. In fact, it becomes more and more difficult to “blow out” a ventilation duct in an ordinary apartment building with natural draft. This is due to the fact that it is gradually clogged with dust and grease, if it is kitchen ventilation. But since several apartments on the floors “sit” at once on the same mine, draft can also form in the case when a window is opened on the higher floor.

It is through this apartment that everything that comes from the lower floors will begin to come out. Whether someone fries onions or fish there, works with chemicals or smokes, all this can go to the apartment where the tenants wanted to ventilate. This is an example of the reverse thrust that such devices save from. The non-return valve will simply prevent these odors from entering your home, because it will be securely closed.

Organization of ventilation in the apartment

What will happen to those odors that need to be removed from? By themselves, they can also go out ... through the window of the apartment, which is located above, if you do not get rid of them forcibly. To do this, you need to install an exhaust hood over the stove or a fan in exhaust hole. But it is in tandem with these devices that you must work check valve. It will prevent the flow of air from the hood to you, but as soon as the fan in your apartment starts, the valve will open its doors and the air path will be free. Of course, there is no guarantee that you will not bring a "stench" into someone else's apartment, where you have not yet installed a check valve, but you will definitely save yourself from trouble.

Table: Popular models of check valves for ventilation:

How the check valve works

Most check valves operate automatically. As soon as the fan starts, there is pressure on the petals or curtains, which causes them to open. That is why it is important not to confuse which side to put this valve in the hood. No matter how you install it, the doors should open away from you, not towards you.

Structurally, check valves are made in the form of a round or square section. They must be inserted into the gap of the ventilation duct. If the air duct runs horizontally, then the valve must be installed so that its flaps are located vertically. If a vertical section of the ventilation passage is chosen for installation, then the flaps or shutters of the damper should be located horizontally, that is, across this channel.

Check valve device. Its operation when the fan is running

For effective operation of the check valve, its opening elements must be provided with a counterweight. As soon as the thrust in the normal direction disappears, the counterweight must bring the doors to the “Closed” position so that odors do not penetrate into the room and drafts do not form. When the valve is installed in horizontal position, then sometimes it is enough either to have a reverse thrust, or just gravity, so that the leaves close by themselves. But as soon as the fan starts blowing air from you, they rise and let it through.

The flaps, as well as the check valve body, are often made of galvanized iron. Such a valve may make noise during operation, so for home use it is preferable to use plastic structures. You also need to pay attention to whether the valve has rubber gaskets. If they are, then this indicates that they will be practically silent and quite tight in operation.

Check valve design

In air ducts round section often used designs of the "butterfly" type, having two flaps on the same axis, passing exactly in the middle of the duct. There are also single-leaf designs, where the axis to which the round cover is attached - in the form of a flat disk, is somewhat offset from the center of the ventilation section.

With a square section of the ventilation passage, check valves are often used, similar in concept to blinds. Only the latter are controlled not with the help of some special mechanisms, but precisely due to the oncoming air flow.

Check valve, natural ventilation

Of course, there are check valve systems with electric control, whose operation is synchronized with turning on the fans and adjusting their speed. Such systems protect against drafts well, but at the same time the ventilation duct will be idle while the fans are turned off. That is, it will not be able to work in the normal exhaust mode, since it will simply be blocked by the flaps of active check valves. So if the dual use of the ventilation system is meant - in the form of natural exhaust and forced ventilation providing outflow, then you need to consider a system of passive and active check valves. And entrust such a thing better specialist who could design ventilation system fully.

Ventilation grate as a non-return valve

If we consider the non-return valve as a protection against the penetration of mechanical particles and insects, then a grill on the vent will work fine instead. Sometimes such gratings, which also have a decorative function, are supplied with a barely noticeable mesh of nylon or other synthetic fiber which is almost transparent or imperceptible. Through such protection, not only flying insects that accidentally got into the ventilation shaft from the street, but also household insects recognized as pests will not get into the apartment. If the grill is completely absent, then even larger uninvited guests - rodents - can get into the apartment.

Coarse mesh does not prevent the passage of air, but a fine mesh can become clogged with dust and grease, which will settle on it from the side of the apartment. In this case, you will have to dismantle the grate and, having removed the mesh from it, subject it to cleaning or replacement. This is not always convenient, so you can do it instead fine mesh check valve. For its own manufacture, it will not be necessary to intervene in the design of the ventilation duct, and if something has to be dismantled, it will only be a decorative grille. It is she who has to be modernized so that she works as a check valve.

Installing a ventilation grate, as a check valve

To do this, you need to take the film medium hardness and reinforce it reverse side gratings with glue. Next, you need to apply a longitudinal slot on it or cut it crosswise diagonally. In the first case, two wings will be obtained, in the second - four triangular petals. When air is blown, they will deviate and allow its flow to pass away from the grate. If a reverse draft is formed, then the petals or flaps will cling tightly to the grate, blocking the access of air from the ventilation duct to the apartment. Now it remains to install the fan itself in front of the grate. In front of the fan, you can put such a grille (or more beautiful) for aesthetic purposes. Naturally, such a grille is simply obliged to have large cells so as not to impede the operation of the fan.

If it is not possible to mount a non-return valve and a fan on the hood with your own hands, then you can pick up ready-made components and purchase them. With a certain variety of industrial designs of check valves, this will not be difficult to do.

How to choose a check valve for your ventilation system

There are several selection criteria for a check valve:

• sectional shape of the duct;
• size of the duct section;
• product material;
• constructive execution;
• the presence of a fan in the kit;
• manufacturer;
• price.

The shape of the cross-sectional ducts are square (rectangular) or round. Depending on what kind you have in your house, you need to choose the type of check valve. Even if the vent is covered with a square or rectangular grate, it doesn't mean anything. To appreciate what shape the ventilation duct itself has, you need to unscrew the grate and see what exactly the space behind it is. If it leads to the ventilation duct, then you need to understand what its continuation is.

Check valve and grate for ventilation system

If a square duct comes out of it, then a check valve will have to be mounted in it. Then you need a square section design. If the air duct is round, then the valve must have the same shape in order to fit exactly into the hole. Sometimes the ventilation device is such that the exit from the cylindrical duct is made in the side wall, and it has square shape, so the appearance of the box itself can also be deceptive, like that of the grate.

Next, you need to measure the dimensions of this ventilation passage and, in accordance with these measurements, choose ready product for subsequent embedding in the design. In addition, you also need to choose the right material from which the valve will be made. Quite cheap and simple butterfly valves are often made of galvanized steel. Almost all ventilation ducts in apartment buildings made from the same material.

Integrating such a "butterfly" into the system is not difficult. The design of such a valve is simple: there are semicircular plates on the axis, which are pressed out by a spring when they are not exposed to air flow from the fan. As a rule, this design is used in round ducts. For square ventilation pipes more often automatic blinds are used. They have several spring-loaded plates, if the design of such a valve is vertical. Horizontal valves use weights and counterweights.

If the valve is close to the ventilation grille, then you can choose plastic version because it makes less noise. But such structures are inferior to steel in strength.

Kit or separate check valve?

If you didn’t have anything in the hood before, then it’s better to opt for the kit, since the parameters of the check valve will perfectly match the characteristics of the fan. If you are already using a fan, for example, built into the hood above cooker, then it is quite possible to choose a suitable check valve for its characteristics. At least the stream that comes out exhaust hood must open the valve flaps. If he does not have enough power for this, then this means that the valve is selected incorrectly.

How to secure your apartment when choosing a non-return valve

If a check valve is purchased separately, then many may pay attention to the fact that some of these products are explosion-proof. This parameter should not be neglected if you use gas appliances. Whether it's just a stove or another column for heating water - it doesn't matter. The main thing is that in the event of a gas leak, such a valve does not give a spark when closing or opening the valves, that is, when metal parts rub against each other. Indeed, in the event of a leak, the gas rushes, including into the hood, where it mixes with air. And it is the gas-air mixture that is explosive, since it contains oxygen that supports combustion. accumulated in ventilation ducts dust is an excellent medium for the spread of fire. That is why it is important that the design of the valve is explosion-proof.

Such a valve can block the access of fire or smoke through if a fire occurs in your house in your riser. Both non-combustible plastic and metal will cope with this.

Fires and gas leaks are emergencies that don't happen every day. But even under such a set of circumstances, a check valve can help you out of a lot of trouble. But much more often, it will simply create the comfort of your stay in the room, eliminating drafts, unpleasant odors and insects. Just don't forget about decorative grille, which also contributes to the power of the air flow. If you take into account all the parameters correctly, you can make yourself an excellent ventilation system.

The non-return valve is used to prevent backflow of air in ventilation systems. When turning off the ventilation system, it must not be allowed that through exhaust channel cold outside air. The non-return valve will prevent cold air from entering the premises, and also protect the ventilation system from fluff, dust and insects.

Also, the air check valve is used in household exhaust systems ventilation. It happens that the smell from other apartments comes from the hood in the bathroom. This is the smell of cooking food or cigarette smoke. In such cases, it is recommended to install an exhaust fan with a non-return valve. Thus, the check valve will not allow air from the shaft to enter the room when the ventilation is turned off. When the fan is turned on, air is expelled into the shaft.

The check valve can be round and rectangular. The most common is a round check valve of the type " butterfly". Two petals are mounted on an axis that divides the valve section in two. The petals are spring-loaded in such a way that they allow air to pass in one direction. When the air flows back, the petals close. The minus of the "butterfly" is the likelihood of freezing and jamming in one of the positions.

Also the role of check valve exhaust ventilation can play outdoor . The inertial grille is designed in such a way that the blinds can only open in one direction, closing when the hood is turned off.

The RSK non-return damper with spring-loaded blades ensures automatic closing of round air ducts when the fan is switched off. The check valve can be installed in any position. The body and blades of the non-return valve are made of galvanized steel sheet 0.7 mm thick. One of the blades has a vibration damping seal to prevent noise when the valve is opened.

The purpose of the check valve of the ventilation system is to allow air to flow in only one direction. Install it in order to prevent the ingress of unpleasant odors, smoke, moisture back into the room. The principle of operation of such a mechanism is as follows:

a) open position; b) closed position.

Ventilation of an apartment building is a rather complex, specially designed system. It will work effectively only if the conditions for air circulation in the apartments and throughout the house are as close as possible to those laid down in the project. And this implies, for example, the presence of gaps of the order of 2 - 3 cm under interior doors and leaky windows.

Since most apartments now have airtight plastic windows, and the doors between rooms are often tightly closed (especially bathroom and toilet doors), ventilation efficiency is often reduced.

Even more, improper circulation is affected by redevelopment, when the size and shape of the ventilation ducts are often violated. This is where complaints come in. bad smell, mustiness and cold drafts. This may be a consequence of pulling air from the entrance through the cracks in front door(in general, the circulation in the entrance is a separate big topic).

But most often, smells from neighbors enter your house through the ventilation system. It is very likely that installing a check valve will solve the problem. Most often, such a mechanism is appropriate in kitchens. It is most reasonable to install it directly in the outlet of the ventilation duct.

It is very important to understand that if the type of non-return valve is chosen incorrectly, air circulation may deteriorate to its complete cessation.

Watch the video of the valve manufacturing process:

The air valve plays a key role in the ventilation of the apartment. If the ventilation installed in the apartment does not function well, then part of the air flow returns from the common house channel back to the living quarters. Accordingly, an unpleasant smell is clearly felt in the apartment. This phenomenon is typical for bathrooms, bathrooms and kitchens. You can solve the problem by installing a check valve in the ventilation system. You can purchase a factory product or make a design with your own hands.

What is a check valve

A device that is installed in the ventilation system to prevent the return of air flow is called a check valve. In other words, reverse thrust is eliminated. In addition, this design prevents insects from entering the apartment, protects living quarters from dust and drafts. Regardless of the type and design features, the check valve works in automatic mode and does not need additional settings.

The principle of operation of such devices is quite simple. In the center of the valve is an axis on which the damper is mounted. When the hood is operating, the damper opens slightly, and the air flow from the apartment goes into the common house ventilation shaft. When the fan is turned off, the damper closes the duct flow by gravity, preventing backdraft. In apartment buildings, check valves in the form of a "butterfly" are widely used. This double-leaf design can be from 100 to 315 millimeters in diameter.

Varieties

These devices may differ in shape, principle of operation and method of installation. Let's look at each type in more detail.

• Installation. The air damper can be installed both vertically and horizontally. It depends on the location of the duct. For example, if the duct is vertical, a horizontal check valve must be installed. This will provide more efficient work devices.

• The form. Valves can be round or rectangular. Recommended throughput such a device can vary from 4 to 6 m / s. The design can be purchased separately or paired with a hood.

• Operating principle. The damper plays a key role in the operation of the check valve. It can be of two types: spool or disk. The first type is designed to work with liquids, so it is not suitable for ventilation. We are more interested in the second option - a disk or plate to prevent reverse thrust.

The non-return valve for ventilation can have a heating function. This option prevents ice and condensation. The effectiveness of this design in apartment buildings is questionable.

The ventilation in the apartments does not come into contact with the outside air, so you are unlikely to need heating. In addition, such devices are more expensive and more difficult to install with your own hands. Therefore, do not succumb to the persuasion of sellers and purchase regular models.

How to choose the right check valve

The functionality of the entire ventilation system will depend on the choice of the check valve. Therefore, the choice of these devices must be approached very responsibly. The first thing you should pay attention to is the mobility of the damper. It should rotate freely on the transverse axis. Thus, the non-return valve will operate even from a slight movement of air.

The second parameter worthy of attention is the cost of the product. Usually the price consists of the following points:

• Valve size and section type;
• Material;
• manufacturer popularity.

Almost 30% of the price depends on the last parameter. It is worth considering that valves made by eminent manufacturers differ in workmanship. Therefore, saving when choosing is not worth it. In addition, more expensive models usually come with an exhaust fan.

The efficiency of the check valve depends on the fan power. If the draft of the air flow is insufficient, the check valve will perform the function of a conventional damper. The power of the hood should be commensurate with the internal volume of the room. For example, an exhaust fan with a power factor of 10 is suitable for the kitchen, and “sevens” can be used for the bathroom and toilet.

We make a non-return valve with our own hands

If you do not have the desire to spend money on purchasing a check valve, you can do it yourself. It’s worth clarifying right away that you won’t be able to completely avoid costs, you still have to buy an exhaust fan. So, the check valve manufacturing scheme is as follows:

• For the foundation you will need durable material. You can use thick plastic or textolite. A plate is cut out of this material, which fits in size to the ventilation hole. The thickness of the plate can vary from 3 to 5 millimeters.
• Holes are drilled at the corners of the base for attaching the plate to the wall. In addition, you will need four more holes for mounting the exhaust fan. Holes are drilled in the center through which air will flow. The number of these holes and their size are up to you. It is worth noting that the more cells there are, the higher the ventilation throughput.
• The fan is attached to the main plate. To make the structure airtight, it is recommended to install at the junction rubber gasket. In addition, small rubber pads can be installed under fixing bolts. This will reduce noise and vibration when the fan is running.
• Now you can start installing the shutters. To do this, you can use a thick plastic film (at least 0.1 mm) or thin plastic. The film is glued to the base in such a way that it completely covers ventilation holes. Plastic sashes are installed on the base with a whole square. Dividing the square into two equal halves is necessary only after the completion of all work. If you are using plastic wrap, it must be absolutely smooth. Any fold will lead to a violation of the tightness of the structure, respectively, there will be no sense from such an air valve.
• The finished structure is installed in the air duct, and attached to the wall with self-tapping screws or dowel-nails. The gaps between the valve and the wall are sealed with sealant. After installation polyethylene film cut into two equal parts, these will be the flaps of the check valve. To make the cut perfectly even, you can use a mounting knife.

Thus, we have a home-made membrane with a check valve function. The structure works like this:

• At natural circulation, under the influence of the air flow, the flaps open slightly. Thus, the air from the apartment freely enters the ventilation shaft.
• When the effect of reverse thrust occurs, the sashes are hermetically slammed shut without letting air from the general house ventilation into the apartment.
• For forced ventilation of the room, the fan is turned on.

Such a design can last for several years, not inferior in performance to factory models.

It should be noted that not only unpleasant odors, but also small insects. To prevent this phenomenon, it is recommended to glue a fine-mesh plastic mesh or a piece of nylon before installing the sashes. Last option preferred. Capron is easier to clean and easier to replace if necessary.

In fact, it is not so important which version of the check valve you install: purchased or homemade. The main thing is that it provides reliable protection apartments from unpleasant odors.

As you know, the air in the ventilation ducts can move in both directions, which causes certain problems, because cold winter air can enter the room, as well as dust. That is why the system must contain such a node as a non-return valve for ventilation - almost anyone can install it with their own hands.

Thanks to him, the air moves only in one direction, while it is possible to open the valve only during operation, which is very convenient.

Device types

There are several varieties of the type of valves under consideration, but only some of them are widely used, let's consider their features in more detail:

Device Selection Criteria

In order for ventilation with a check valve to work effectively, it is necessary to take into account a number of factors and select products with optimal technical specifications, this is important, since any miscalculations can create many problems.

What to look for when buying

Proper selection of the valve is a guarantee of the absence of failures in the air exchange system and ensuring optimal conditions functioning of all communications.

The most important factors are the following:

• Estimated airflow rate in the system, protective device should open even with minimal movement air masses. This is especially true for natural systems ventilation, where the draft is very small, and sometimes the only possible option to ensure operation is a ventilation grill with a check valve and exhaust fans, this simple device will provide the necessary draft.

• It is very important that the non-return valve for ventilation in an apartment or house is suitable for the characteristics of the fan. The easiest way is to buy both of these products in one case, this guarantees the correct functioning of the system. But if the units are purchased separately, then the thrust created by the fan must ensure the opening of the valve.
• Another important factor is climatic features your region. For example, butterfly devices are prone to freezing during prolonged negative temperatures, so they are best installed indoors rather than on outlet grilles. This will avoid freezing and jamming of the nodes.

Advice! In some rooms, ventilation ducts can become clogged and coated over time, if you have a valve without an electric actuator, then even a small layer of plaque disturbs the balance of the device and causes it to work incorrectly, so do not forget to periodically check and clean the petals.

• It is also important to take into account the characteristics of the system laid in the room. If the ventilation duct is rectangular, then the valve body should be the same, this will greatly simplify installation work, otherwise you will have to make a homemade adapter. The size of communications is also important (100 by 100 pipelines are most often used, but there may be other options).

Advice! The best product to buy well-known firms well established in the market. This guarantees the quality of the product and its compliance with the declared parameters.

Some design features

There are a number of nuances that you should be aware of when choosing a particular option:

• According to the installation method, horizontal and vertical type. The first are installed on horizontal sections, the opening direction is selected in accordance with the system, the second option is placed on the risers, and the air direction in it is always from the bottom up.

• If you are installing a check valve, then you should select a product with convenient system fastenings, it is best if it is an option with flanges or clamps
• Another important nuance- the installation site of the structure, if it will be located in outer wall or next to it, it is better to purchase an option with electric heating, this will eliminate the freezing of the blades at low temperatures and prevent the appearance of condensate in the system. If the valve is installed from the inside, then this option is not required.

Conclusion

The non-return valve in ventilation systems prevents the penetration of cold air and dust into the room, allowing you to maintain an optimal microclimate.

The video in this article will help you better understand the features of the type of device in question.