A ventilation grill with a non-return valve is needed to block airflow entering the room. This part helps to solve the problem with bad odors, which appears due to the ingress of air from other rooms or the formation of back draft. Before installing the grate, it is advisable to study the features of its design and purpose, advantages and disadvantages, get acquainted with existing types, installation and operation rules.
Fan grille with check valve
The check valve grille is an element that includes a protective housing, a fastener, a shutter and an external cover. The damper from the valve can be opened by forced circulation of air masses that move under pressure. The grille is connected to the duct using a flange, it is presented in various dimensions and is combined with devices of any type.
Most gratings are made of plastic, this is the most suitable material, since the part is operated in rooms with a high level of humidity. It most often has the shape of a rectangle, due to a similar design, the grill is able to close not only the ventilation shaft, but also affect part of the wall. The moving part element can take the form of a circle, rectangle, petal or butterfly; it opens only in one direction.
Advantages and disadvantages
The check valve grille, regardless of its type, is one of the most popular elements due to the large list of advantages. The list of pluses consumers include:
- preventing tipping of the traction element and air from the street or from adjacent rooms;
- good noise absorption, reliable protection of space from unnecessary sounds;
- beautiful appearance that allows you to place elements in the interiors of any type;
- lack of problems during installation and during operation, practicality and reliability;
- a wide range and choice, a variety of dimensions, shades and design options;
- reasonable cost of items.
Among the shortcomings, consumers note the risk of freezing grids in winter and the insufficient performance of some models. It is possible to solve the problem with freezing after installing the heater integrated in the fan.
Operating principle
The ventilation grill with the valve operates according to the standard principle: the exhaust air mass passes through the outer cover with the valve and raises the damper. After the pressure drop in the flow, the shutter begins to close and becomes a reliable barrier to unnecessary odors, insects, dust and pollution. This detail is indispensable in kitchen facilities and bathrooms, as well as in rooms adjacent to them.
The check valve prevents the flow of air masses and noise, this is the main difference between such a lattice and the usual counterpart without additional protection. You can install the part both from the outside and from the inside of the building, connecting it to the end side of the duct and sealing the butt elements.
Existing species
Ventilation grilles with a valve are divided into several varieties, taking into account the type and shape of the locking device. Plastic parts are placed indoors because they do not withstand temperature extremes.Metal analogues are ideally suited for installation outside, to prevent freezing, they use special heating.
Gravity Single Casement
Such models are a standard design with a locking element in the shape of a circle or rectangle. Their principle of operation is to shift the part of the damper using an air flow in the correct direction, which then continues to move freely along the duct. Then the valve is pulled to the base of the ventilation grid and closes it. Gravity elements are presented in two types: with an offset axis where the damper is fixed, and with a counterweight of internal or external type. The device must be installed vertically or horizontally, otherwise the cover will not close until the end and will not protect the room.
Petal
Petal variants have a structure similar to gravitational counterparts. They have valves in the form of blinds, the operation of which is based on the principle of gravity. With multiple flaps, such appliances function much better. Valves on them can be installed only over the entire area or on one hole.
The ventilation grille with a flap valve is considered the most versatile and practical.
Membrane
Membrane-type elements are the most popular; lightweight and flexible plates are used as sashes. Due to insignificant resistance, they close under the influence of gravity. Due to the simple design and the absence of difficulties during operation, these grilles can be installed in ventilation systems with standard air flow circulation. To prevent deformation of the membrane under the increase in pressure of air jets, the gratings are supplemented with rigid ribs. They serve as a support for the partition during the formation of excess traction.
Butterfly
Butterfly valves include two shutters and close under the influence of springs installed in them. These grilles can be placed in various positions; when choosing, they check in advance the operation of the springs under the influence of air pressure. In more innovative versions, the strength of the springs can be changed. It should be borne in mind that butterfly devices work only in systems with forced ventilation and are not suitable for natural draft circuits.
Selection rules
The choice of a lattice element depends on the design features of a particular ventilation system, in some cases the parameters are indicated in advance. You can also select a part using special monograms designed for specific requirements. For large systems, the main selection criteria are air consumption and speed, so they require custom-made grilles and supplemented with a special regulator. In addition to the requirements in terms of technology, attention must be paid to the aesthetics and design of the elements.
In most cases, the choice of a particular model depends on the shade of the part, the need for adjustable shutters and fine mesh. Additionally check the noise and aerodynamic properties, characteristics and areas for installation, installation location, for example, on the floor, ceiling, wall or door. An important parameter is the absence of problems during maintenance, the dimensions of the duct or hole, as well as the ability to consume air during operation. At the beginning, you must always take into account the dimensions of the ventilation duct and its geometry, as well as operating conditions.
The choice of gratings for industrial premises should be entrusted to professionals. If we are talking about details for apartments or houses, they can be selected independently if there is a project or scheme of a ventilation system.
Installation and operation
A ventilation grill with a non-return valve for streaming natural ventilation is installed on the outside of the wall, some details are allowed to be fixed in the ventilation shafts. At the first stage, the device is connected to the duct using a connecting flange, filling the gap between it and the wall using sealant. After the foam hardens, its excess is removed with a clerical or construction knife.
At the next stage, the grate must be fixed on the supporting surface using dowels or a self-tapping screw. Choosing a fastener is necessary taking into account the weight of the part and the material from which the walls of the building and the body part of the grill are made. After completing installation work, the device can be started in test mode. If the installation was carried out correctly and without errors, in compliance with all requirements and safety rules, the grill will work as stable as possible.
A properly installed check valve grille is an important part of the hood and ventilation system. With its help, you can reliably protect the duct from external flows and create the perfect microclimate in the room.
