- What is the task?
- Manufacturing material
- Appearance requirements
- Participation in the ventilation system
- The difference between supply and exhaust
- Installation system
- Functional features
It would seem that ventilation grilles are an absolutely ingenuous thing. But when studying their assortment, it turns out that these modest products are combined into fairly informative catalogs. So many varieties are needed to fulfill a wide range of functions, including decorative.
What is the task?
Ventilation grilles are used to hide traces of installation of ventilation ducts and get rid of the through hole that spoils the look of the finish. But the decorative purpose is only a component of the main functionality. For example, grilles can trap small objects coming from ventilation, such as insects or dust..
One of the most important functions is participation in the air exchange process. The grilles are also capable of changing and distributing the air flow, normalizing the throughput of the channel, preventing the reversal of the flow, and in some cases, even regulating the air exchange automatically. To carry out such work, a hermetically sealed junction is required, therefore, an installation system for connecting to a wide range of cross-sections of the main channels is a very important indicator for the lattice..
In specific installation conditions, special requirements may be imposed: anti-vandalism, resistance to high temperatures, rationalization of heat transfer (recuperation) or light and sound insulation. So sometimes, under the external simplicity, there is a number of technological solutions that help to solve the maximum of the tasks..
The key difference is the material of manufacture. The restrictions on the use of gratings are quite obvious from this point of view: metal can do what plastic cannot and vice versa. Mainly, mechanical strength is considered: metal gratings are better for large cross-section channels, as well as for walls and floors located in the lower zone.
Plastic is preferable in terms of light weight and more aesthetic appearance. Plastic molding allows you to vary the shape, size and pattern of the gratings in a wider range than metal. However, not every lattice is cast with high quality, many have not solved the issue of providing additional rigidity and strength, for cheap products there is a risk of using recyclable materials. In addition to destructive damage, such gratings are subject to significant deformation, especially at high temperatures..
A separate type of lattice is wooden. Almost all of them do not have the possibility of regulation, and the functionality is divided equally between the decoration of the channel and the direction of the air flow. It should be understood that the need to use wooden ventilation grates is dictated by considerations of maintaining the integrity of the interior, for example, in a sauna. There is no particular sense in using wood for ordinary purposes, and they are very whimsical in care.
The smaller their size, the greater the variety of lattice types. If the grilles for large channels are usually louvered, honeycomb or mesh, then for products less than 40×40 cm, the appearance of a closed diffuser, a flat dissecting panel, as well as a more free choice of the “pattern” of the grill may be characteristic.
Non-adjustable grilles made of metal (cast iron, duralumin) are designed for the installation of exhaust ducts in the floor and walls with stone finishing. In the same category are items made of ceramics, plaster and the like. A more minimalistic look is given by aluminum and stainless steel grilles, especially slot diffusers.
Lattices can be round or rectangular in shape. Basically, this difference determines the appropriateness of their installation: round and equilateral ones look better on monochrome painted surfaces, rectangular ones – if there is a pattern: wallpaper, printing, applications, etc..
Participation in the ventilation system
The ability to restrict and redirect the air flow is ensured by the special shape of the rails and the ability to change their position. The ventilation is not affected in any way by non-adjustable grilles: cast, mesh and the vast majority of wood. However, it is worth knowing that the ability to adjust the flow can also be achieved due to the controlled damper, but qualitatively distributing air throughout the room is possible only due to the shape of the grate itself. Usually non-adjustable grilles are installed on exhaust openings.
Non-adjustable plastic grilles
Diffusers (anemostats), reflecting the air flow from the supply duct and scattering it along the walls, demonstrate themselves in the best way in the matter of air distribution. Swirl diffusers are capable of changing the direction of the flow, while disc diffusers can only regulate its amount. The louvers of the grilles can also be tilted at different angles to change the flow capacity of the channel. Double-row louvers allow you to direct the flow and change its intensity independently of each other. Instead of the inner row of louvers, a movable flap can be installed that regulates the flow and the intensity of air exchange.
1 – anemostat; 2 – vortex diffuser
A rather interesting principle of operation is incorporated in the design of inertial grids. Their louvers are balanced in such a way that the grille closes the duct in the absence of flow or its reversal. Such grilles do not require stopping the check valve, which in ventilation systems without forced air exchange is necessary to eliminate back draft. This is especially important in order to exclude the exchange of odors between rooms or different apartments..
The difference between supply and exhaust
It is very beneficial to use the same devices for supply and exhaust ducts. This, first of all, helps to more harmoniously fit the technical elements into the interior. On the other hand, the installation scheme will be more uniform..
Universal fan diffuser
For exhaust grilles, the flow rate adjustment is not required, they generally have excess capacity. Here, the installation of adjustable diffusers is quite acceptable, but unregulated ones are almost never installed on the inlet openings. The situation is similar with lattices: there are universal models, there are simplified ones. The main difference lies in the fact that the supply inlets have a filter, a device for adjusting the flow and direction, while the exhaust ones are equipped only with gravity shutters or a check valve..
There are quite a few types of grilles with rigid wall mounting. Basically, either the entire body or its outer part are removable so that access to the maintenance of the ventilation duct remains. The presence of internal installation also helps to correctly place all the necessary equipment, including adapters, adapters, adjustable dampers, etc..
Small lightweight gratings have a simple scheme of attachment to the hole walls using spacer lugs. This is typical for most diffusers and universal supply and exhaust plastic grilles. Mounting frames can be built into the wall under the grilles of larger sizes. The entire grille is fixed rigidly, either if it is an unregulated exhaust air, or if it is a slot diffuser.
We must not forget about special grilles, which are cut into doors or window sills as overflow channels. The first is practiced so as not to create an additional gap in sound insulation, the second is to eliminate fogging of windows. In both cases, the grating has a direct attachment to the array, into which it is cut. A separate type is gratings for stretch ceilings, which are installed in sleeves pre-soldered into the canvas and can be fixed to the main ceiling if necessary to hold significant weight.
There are also a few special and interesting optional grill fittings. The most common example is a mosquito net for supply ducts or a filter that traps dust from the incoming air. The transfer grilles are characterized by a special V-shape of the slats that impede the propagation of light between rooms..
Frost and heat resistance, shock and moisture resistance can be separately regulated. Some grilles are equipped with a condensation protection system. One of the more interesting solutions is to combine a circular grille or diffuser with a point light source..
Among the most modern and sophisticated devices, the external wall transfer grilles with integrated counter heat exchanger are worthy of mention. Basically, they work in pairs for exhaust and supply, cyclically changing the direction of the air. Despite the simple appearance of a conventional diffuser, these devices are very complex inside and help to improve the energy efficiency of the ventilation system without reducing air exchange..