Non-return valve for ventilation: application and selection criteria

Everyone faced a situation when, being in his apartment, you unmistakably determine which dish is being cooked by the neighbors or, worse, you smell the smell of tobacco. This occurs because of the ingress of extraneous odors into the apartment through the ventilation duct at the back pull. To prevent this from happening, it is recommended to install a non-return valve for ventilation, which blocks the movement of the air flow in the opposite direction and contributes to the effective removal of exhaust air from the room.

Check valve for ventilation: device and classification of mechanisms

Consider how the reverse ventilation valves work. The design of the check valve for ventilation is quite simple: the blades of the valve are located on the same axis so that air can only flow in one direction. If the flow direction changes, the valve closes. In addition to the function of blocking the return flow, the valve can be used to regulate the supply air volume by changing the duct section.

Air check valves for ventilation are distinguished by the following characteristics:

• material for production – in various air ducts valves made of plastic or galvanized steel are used;

• by design – lattice, butterfly, petal or membrane. In the lattice device with a non-return valve for ventilation, louvers are provided that open under the pressure of the air only in one direction, which eliminates the reverse flow. Such lattices with a check valve can have various shapes and designs and are installed at the inlet or outlet of the ventilation duct. The butterfly valve device resembles a butterfly of two plates, fastened with a spring. The diaphragm check valve is a thin valve that deflects even with a light airflow and sticks to the ventilation grill when the flow changes its direction. It is applied, as a rule, with natural ventilation. A flap check valve is similar in principle to a diaphragm valve, but it is manufactured as a rigid valve fixed on an axis, which rotates under air pressure and opens or closes the channel, depending on the direction of flow;
• in shape – rectangular or round. Choose depending on the shape and size of the section of the duct, which will be installed check valve. Domestic round valves are produced with a diameter of 100 mm, 120 mm, 125 mm, 150 mm and above. The check valves used in industrial ventilation systems have a diameter of from 150 mm to 1000 mm.

• control method – the valves in their device are manual and electric. The non-return valve for manually controlled ventilation is manually controlled by a lever or valve. The electric valve functions in conjunction with other devices of supply and exhaust ventilation and automatically regulates the flow of air;
• installation method – the device can be mounted vertically or horizontally, depending on the design of air ducts;
• capacity – the volume of air passing through the valve per unit of time may be different.

Regardless of the type of ventilation, whether it is a natural supply and exhaust or a mechanical system, reverse thrust may appear in it.

For natural ventilation, where ventilation ducts are used, check valves are used that are particularly sensitive to changes in the direction of air masses. For high-quality air exchange, it is better to install a check valve for ventilation simultaneously with the installation of ventilation channels.

Installation of a check valve for ventilation in the apartment, where natural air circulation takes place, is made in the walls between the rooms. Usually the holes in the walls of the apartment are made near the doors and lattices of check valves are installed in them that control the air flow.

Supply ventilation, the design of which consists of an air duct mounted in an external wall, is provided with an air intake grille from the street side. The filter cleans the outside air, and the check valve device regulates the supply air volume and contributes to maintaining the temperature in the room. At the same time, the installation of a check valve for forced ventilation makes it possible not to resort to additional ventilation of the rooms where plastic windows are installed, air exchange will be sufficient.

Installing a check valve for ventilation in the kitchen allows you to block, even when the hood is turned off, the flow of extraneous odors from the back pull, but it does not prevent the exhaust air from being removed from the kitchen into the ventilation channel.

To ensure that ventilation continues to work, the air ducts are supplied with ventilation grids with a non-return valve for natural ventilation with openings through which exhaust air is removed without the use of exhaust hood. Recently, an exhaust hood with the removal of polluted air directly outside is in demand. From the outside, the air duct is equipped with an exhaust ventilation check valve, which prevents outside cold air from entering the room.

In the bathroom, mildew and damp smell are often observed. This is due to inefficient ventilation. The bathroom room first of all needs high-quality removal of moist air and prevention of odors from other apartments. And given that the bathroom can be used by neighbors for smoking, tobacco smoke with poor air exchange can get through the ventilation shaft and into your bathroom, and hence in the apartment. Installing a check valve for ventilation in the bathroom will solve the problem of getting there odors.

To determine which non-return valves for ventilation are better, you need to be aware of the main selection criteria:

• the device should work even with a small movement of air, which is typical for natural ventilation. The thrust with this air exchange is small, so for efficient air exchange it is better to install an exhaust fan in a complete set with a ventilation grill and non-return valve;

Important! It should be understood that with an incorrect selection of the model of the check valve, the air exchange in the room may deteriorate, up to a complete cessation.

• The parameters of the non-return valve must correspond to the characteristics of the selected fan: for example, if the valve is 150 mm in diameter, then the fan must be of the same diameter. The fan power should be sufficient for the generated air flow to ensure the opening of the valve petals;
• environmental conditions. Some check valve devices are not able to operate at low temperatures. Therefore, they are mounted only indoors;
• features of the ventilation system. If the air duct of the system has a rectangular shape, for convenience of installation, it is provided to install a check valve for ventilation of a rectangular section. Dimensions are selected also taking into account the cross-section of the box. For domestic use, air ducts and check valves for ventilation of 100 mm are often used.

Helpful advice! To be sure of the quality and compliance of the device with the characteristics, it is necessary to purchase non-return valves from reputable manufacturers.

The network of hypermarkets “Leroy Merlin” offers a wide range of products for the arrangement of ventilation from proven manufacturers. You can get acquainted and order a suitable check valve model on the official website of Leroy Merlin. In Leroy Merlin stores, you can directly consult with experts and purchase non-return valves of various models and sizes.

Popular models offered by the Leroy Merlin network of check valves for ventilation:

In addition to check valves, the Leroy Merlin network offers a large selection of ventilation grilles, both internal and external, of various shapes, sizes and colors, thanks to which they can additionally serve as a decoration.

To properly install the device with your own hands, you first need to determine what place the check valve will occupy in the ventilation circuit.