Silent axial fan. Duct fans. Varieties of duct fans

Traditionally, it is considered that the ventilation system is noisy. In fact, this is not always the case. The noiseless duct fan with a special sound-absorbing design operates very quietly, so it can be installed even in rooms where special requirements are placed on silence.

Why is a Silent Extractor Fan Quiet?

Silent duct fans for exhaust have a special housing structure. It is made of plastic or metal with special noise-absorbing perforation, or with a glued soundproofing material. On the inside The device contains a soft layer that prevents vibrations and does not allow sound from moving air to spread. In addition, the special shape of the blades allows you to direct the flow without whistling.

Many manufacturers offer silent duct fans, the price of which often depends not only on quality and efficiency, but also on the degree of brand promotion. Our store offers a select range of fans, the cost of which is fully justified by quiet operation and reliability.

Benefits of Silent Design

To achieve quiet operation, the design of the fans is adjusted with maximum precision. Thanks to this, such a system has received additional advantages:

high air intake efficiency;
minimum energy consumption;
large operational resource;
smooth speed control;

Thanks to the thoughtful design and quiet operation, it is quite possible to install in a room or bedroom, not to mention commercial and industrial facilities.

For which duct can I buy a silent duct fan

The most popular are silent fans for 100 mm hoods. They are suitable for round ducts with a diameter of 100 mm. Since the electric motor provides efficient air injection, even the minimum patency of the channel is quite enough to ensure freshness in spacious room. Usually they are chosen for installation in apartments, since they have a small air duct that can be hidden behind a false ceiling or wall.

Silent exhaust fans 125, 150, 160, 200, 250 and 315 mm are used for commercial and industrial installations. Their performance is much higher, which allows for a more intense flow. For domestic needs, silent 150 mm exhaust fans are usually chosen. This power is quite enough for a cottage and other low-rise buildings.

Original fans at a good price

In our store you can buy duct silent fans for exhaust from leading manufacturers. We are confident in the quality of the range presented, so our customers have access to reliable and efficient devices that can last for many years. We always have favorable prices, so by choosing our store, you can purchase equipment that will provide clean air at minimal cost.

Modern ventilation equipment is able to provide a healthy microclimate in any room. But often this is achieved at the expense of living comfort, since the noise associated with work causes at least discomfort and irritability, and even chronic fatigue.

Silent duct fans for exhaust will help you get out of the situation. We will talk about how to correctly select an extremely quiet device designed for installation in an exhaust duct or a hole drilled in a wall. We will show you how to understand the assortment, taking into account the characteristics and features of the work.

Silent duct fans on the market are traditionally divided into different categories, subspecies. But a healthy microclimate largely depends on performance. One of which, noiselessness, is even included in the name, that is, the buyer always needs to make a choice by determining a number of parameters.

The main ones are:

noiselessness;
performance.

If you like silence, then you need to start the search with the first characteristic, since it is it that has a significant impact on the comfort of living.

Instrument noise criterion

According to sanitary standards SN 2.2.4/2.1.8.562-96, in residential premises and a number of others, the noise level should not exceed a moderate 30 dB during the day and 20 dB at night. Which are comparable to a quiet whisper and in many situations will be quite appropriate for kitchens, bathrooms and other premises.

Each duct fan on which the complex is made is noiseless. special works. These include the isolation of structural elements from each other, for example, the engine from the body, as well as the optimization of the aerodynamics of the blades, the channel through which polluted air masses move

But still, you need to remember that often the sound emitted by these fans at 30-35 dB, even from a distance of several meters, will annoy users. This is especially true for situations where there is a bedroom or a nursery next to a toilet or bathroom equipped with ventilation equipment.

As a result, you should be aware that really silent, and without any compromises and tricks of marketers, are considered models in which such a performance does not exceed 25 dB. In this case, the sound of a running fan is comparable to a very quiet whisper.

Since the good is always the enemy of the best, when buying, you need to remember that models that belong to the category of market leaders in terms of noiselessness emit no more than 20-22 dB.

And although the advantage over conventional low-noise models may seem insignificant, it may well become decisive after several years of operation. Those. when the performance of the device decreases, the bearings begin to be produced, the air channels become clogged with dust, and the anti-noise gaskets wear out.

All silent units shown are suitable for use anywhere in the canal, making them versatile and efficient in all conditions.

Comfortable operating sound ventilation equipment can provide a number of integrated solutions for engineers.

These include the following:

using high precision bearings- such high-quality and balanced products exclude beating, as a result of which there will be no vibration, which, when resonating, can significantly amplify the sound;
high technology blades- one of the reasons for noise is the aerodynamic component, so the developers, wanting to make the sound comfortable, carefully select the number of blades, optimal angles of inclination, and also carry out precise balancing of the impeller elements during manufacture;
use of technological buildings – quality material manufacturing (metal, plastic) eliminates the vibration of individual parts and assemblies, aerodynamic noise of moving air;
using vibration damping pads- Quiet operation is also achieved by using special types of rubber as gaskets to prevent contact between the housing itself and the attachment points of the electric motor to it.

Gaskets steel important element structures, they isolate the fan housing from the duct, wall.

Bearings, blades and special housings and gaskets - all this reduces vibration, turbulence of air flows and their resonance to insignificant values.

Today, it is no longer uncommon to finish ventilation shafts with modern soundproof materials. Reduces noise and secure fastening electric motor to the body. The power plants themselves are common and are used on all types of fans.

Fan performance figures

This characteristic is considered one of the most important, as it is interconnected with noise. It is clear that the higher the performance, the louder the electric motor and related sounds sound.

As a result, it’s not worth it to thoughtlessly buy, to the kitchen, to the toilet on the principle “you can’t spoil the porridge with oil”, as this can result in a decrease in living comfort and financial losses.

But avoid negative consequences not difficult. That is, the optimal power can be calculated knowing that such an indicator should correspond to the derivative of the volume of the room and the air exchange rate.

For example, the volume of a shower room is 5 m³, and the recommended air exchange rate, according to SNiP, is 7-9. And to calculate performance, you just need to multiply Cubic Meters for any multiplicity. The result is 35-45 m³ / h.

Being the most important characteristic of all kinds of duct fans, the performance must be calculated correctly, since an attempt to achieve silence due to a lack of power will lead to the fact that you have to buy a new unit. And excess power leads to excessive consumption of electricity, the occurrence of drafts and an increase in the volume of work.

Different perform a number of important options. Therefore, so that during operation you do not have problems with the device, you should pay attention to a number of characteristics when buying.

Which, in any situation, include:

design safety;
functionality;
geometric dimensions;
price.

Although all of these features are traditionally in the shadow of the main performance characteristics (performance, noise), they cannot be called secondary. Since each of them significantly affects the features of ventilation equipment.

The Importance of Safe Design

Since duct-type fans are designed for ventilation in all kinds of rooms, they often have to work in difficult conditions. Which create high humidity in the bathroom, kitchen, toilet, the presence of fat particles in food preparation areas and increased dust in other rooms.

All of the above has a significant impact on the performance, durability of the unit. And most importantly, it affects the safety of living. Since particles of moisture, fat can always lead to a short circuit and other negative consequences.

Each used must be at least splash-proof, and even better moisture resistant. effective measure, allowing you to take care of your health, is the purchase of a unit operating from low voltage, which is considered to be 24 V, but its power will not be sufficient in all cases.

An important advantage of any duct fan is that it can ventilate air in several rooms at once, regardless of its location. And all you need to work effectively is correct installation and enough power

And most practical solution will be the purchase of a fan with a protection class of at least IP34. As a result, the user will protect himself, his loved ones from all sorts of unpleasant cases.

Importance of equipment functionality

Modern duct fans designed for or in the kitchen are quite technologically advanced and the buyer has the right to choose a device with the most suitable operating mode, which can be:

standard;
auto;
autonomous.

In the first case, it is connected to the same electricity switch as the lighting of the room in which it is installed. As a result, both lamps and ventilation equipment are turned on simultaneously.

The shutdown procedure takes place in reverse order, that is, after turning off, the ventilation and lighting of the room stops.

The method described above is quite convenient and effective for use in, but is already considered obsolete. The reason is that short ventilation cycles are not able to successfully cope with high humidity, for example, in the bathroom.

The purpose of all kinds of fans of this type is identical, that is, they, being in the channel, must divert air masses outside the premises, but they cope with this task in different ways. And it all depends on the level of functionality of products

Some species can work autonomously, determining the level of pollution on their own. Less technologically advanced fans operate on the basis of programs embedded in their timers, and the simplest products ventilate in the interval between switching on / off that the user performs.

This feature does not allow you to effectively cope with the replacement of air masses with fresh ones or leads to an excessive consumption of electricity, and an impressive one. The automatic ventilation option implies that the fan has a timer that allows you to set the ventilation period, taking into account the conditions in a particular room.

As a result, the procedure looks like this:

The user, entering the bathroom or any other room with a fan, turns it on by pressing the switch button.
The ventilation device removes polluted air masses, even after the person leaves the room.
The stop occurs automatically after a user-defined period of time has elapsed.

The advantage of this type of equipment is the ability to choose optimal mode for all cases. At the same time, user participation in the work is minimal.

The most modern are duct fans that can carry out air exchange in autonomous mode. What allows you to do the presence of sensors (for example, humidity). The signal from which leads to the on / off of the fan itself.

Although all duct fans are hidden from view, this is not a reason to save on the quality of manufacturing materials or anything else. Since, in many respects, noiselessness, durability, efficiency depend on it.

The advantage of the latter method is the greatest efficiency. That is, the air is always clean, while user participation is not required, it is also important that there is no excessive consumption of electricity.

Shape, size and cost

Today, fans are supplied with various form buildings.

Which are:

round;
rectangular;
square.

But you should know that for domestic purposes, mainly products belonging to the first variety are used.

Rectangular and square counterparts are most often classified as productive industrial devices, so the owner of a house, apartment, office is unlikely to have to deal with them. The only exception will be cases where a vertical ventilation tube in a separate box.

Main geometric parameter household duct fans is the installation size. For example, the specified characteristic is always indicated on the body and in its technical documentation, as it may well affect performance.

In addition, the indicated dimensions are standard values, which makes it easier to choose a fan.

The cost of models also depends on the features. For example, fans equipped with a metal case, with the same features, are several times more expensive than their counterparts with plastic cases, although this does not guarantee the possibility of obtaining much more benefits.

Therefore, you should know that for domestic purposes, devices that are marked 100, 125 or 150 mm will be optimal. For ventilation in non-standardly large residential premises, restaurants, offices, options that indicate 160 mm or 200 mm are suitable. Products of the big sizes belong to industrial.

Since the performance, functionality of fans, the quality of materials of manufacture and the amount of work that ensures noiselessness are radically different, their price also differs significantly.

As a result, for an inexpensive option, you will have to pay a quite moderate amount. And for a model that can work autonomously, that is, equipped with a humidity sensor, a controller and capable of operating silently for many years, you need to pay many times more.

For comparison: for the money you can buy quite a decent smartphone. However, the most affordable fans are not the best option. After all, they are not designed for a high level of safety, durability.

Types of duct fans

Today, at points of sale, you can find fans that are structurally related to several varieties.

These include:

axial, less often they are called axial;
radial;
centrifugal.

Each type has its own advantages and disadvantages, so you should be aware of them.

Group #1 - axial fans

A characteristic feature of this variety is the direction of air flows along the axis of the electric motor, on which the impeller is located, which is responsible for the movement of air masses.

Any axial duct unit is the simplest type of duct fan. Nevertheless, they are quite effective, economical. In addition, among such equipment there are a lot of modern technological and safe models that can provide a sufficient level of living comfort.

The main advantages of axial fans for all kinds of hoods are:

low performance required to move air masses;
economical electric motor;
simple construction.

The listed features make the units related to the presented type the most silent without any additional measures. That allows us to rank them among the most affordable, and therefore in demand for any household needs.

The main disadvantage is considered to be low performance, which is still quite enough to solve various local problems.

Group #2 - centrifugal fans

Such devices are more technologically advanced than the axial ones described above. This is evidenced by the fact that the air flows do not move straight along the axis, but due to the special shapes of the impeller blades, they are mixed, compressed and directed towards the housing.

In this case, a rarefaction effect is created behind the trailing edges. This leads to the fact that there is a rapid absorption of external air currents.

Radial units are more efficient than their axial counterparts. When choosing them, it should be remembered that there are 2 subspecies of such fans and the products with forward-tilted blades are considered the quietest, moreover, they are significantly more economical than their counterparts with backward-tilted blades.

So, the radial type of fan designed for exhaust can be of two types:

with shoulder blades tilted forward;
with shoulder blades tilted back.

The first variety is optimal for silent operation, moreover, it is more economical, and by an impressive 20%. But if important parameter is performance, then it is better to purchase fans whose blades are tilted back.

An important feature of each radial fan for any type of hood is compactness. This advantage is especially valuable when the installation space is difficult to access or there is not enough of it.

Group #3 - centrifugal fans

This is the most modern, quietest and most productive type of duct fans. Their principle of operation is similar to radial counterparts. That is, increased pressure is created closer to the body, and a rarefied space is created in the center, which leads to more efficient suction of external air masses.

Centrifugal fans are the least known type of fans. Nevertheless, such products are among the most technologically advanced, productive and silent. The only negative is that they are too powerful for small bathrooms, toilets and even kitchens in ordinary apartments and even many private houses

Features of a design and the principle of work does the quietest. In addition, they can be installed directly in the ventilation shaft of the apartment, which eliminates negative impact on the aesthetic properties of the room.

And most importantly, this helps to increase the power of units of this type and reduce the impact of moisture and dust on them, which prolongs the resource.

Regardless of the type of duct fan, its performance and functionality, it is recommended to clean it from dirt every 1-3 years. It is desirable to carry out the same operation with bearings, which will extend the service life, as well as increase safety.

A significant disadvantage of any centrifugal fan is its high performance, as a result of which they can only be used in rooms from 15 m².

Conclusions and useful video on the topic

This video provides an opportunity to get acquainted with what a duct fan is and understand the principle of its operation:

Among modern duct fans, it is quite feasible to find a silent model required power, characterized by durability and safety, and in various price categories. But at the same time, you should have a certain amount of knowledge or you will not be able to get the expected result.

Would you like to tell us about how you chose a silent fan for installation in an exhaust duct? Share what has become the main selection criterion for you personally. Please leave comments in the block below, ask questions and post questions on the topic of the article in the block below.

Updated: 19.09.2019 11:10:35

Judge: Boris Mendel

*Overview of the best in the opinion of the editors of the site. About selection criteria. This material is subjective, is not an advertisement and does not serve as a guide to the purchase. Before buying, you need to consult with a specialist.

Maintain an optimal microclimate in homes and industrial premises allow duct fans. They represent electrical devices consisting of a housing, a motor and an impeller. The main task of the duct fan is to move air masses along the ventilation ducts. This may be the removal of polluted air from the room or the organization of the influx of masses from the street. In each case, a device with a certain set of technical characteristics is required. Expert advice will help you make the right choice.

How to choose a duct fan

The size. First of all, you should decide on the size and shape of the bends. The easiest way to do this is when the ventilation system is already installed. For round pipes a duct fan with outlets of the same shape and suitable diameter is selected. In the case of square or rectangular shafts, it is better to buy appropriate fans.
Performance. The second important parameter is performance. The technical specifications indicate such an indicator as air exchange. It can fluctuate between 100-2000 cubic meters. m/h For a private house, a duct fan with a capacity of 100-500 cubic meters looks optimal. m/h But for retail and commercial premises, more powerful models (1000-2000 cubic meters / h) are required.
Engine power is not always directly proportional to productivity. The more powerful the motor, the easier it is to pump air, the less the load on its components and parts. The power range ranges from 10 to 500 W, it is better to choose models with a small margin. For example, if the project specifies a 130 W fan, then it is optimal to install a 150-160 W model.
Noise level. For residential premises, an urgent problem after installation ventilation system the appliance may become noisy. Manufacturers indicate the noise level in dB (15-100). Many users, in their experience, consider electrical appliances with a noise level of up to 40 dB to be low-noise models. A higher sound load starts to strain, especially when the duct fan is located directly in the room.
materials. As for the materials that are used in the manufacture of devices, most often manufacturers use plastic and metal. Steel cases and impellers are considered more reliable, but they weigh more and cost more. Plastic products win in silent operation, lightness and low price. Owners of private houses prefer to buy them, despite their lower strength.

Our review includes 7 of the best duct fans. When compiling the rating, the conclusions of the expert community and reviews of domestic consumers were taken into account.

Rating of the best duct fans

The VENTS TT Silent-M 200 inline fan perfectly combines high performance (1020 m3/h) and low noise level (36 dB). Experts highly appreciated the moisture-proof design of the steel case with polymer coated. Due to the special design of the impeller, the model consumes electricity quite economically. The optimal combination of all technical parameters allowed the device to become the winner of our rating.

Users pay attention to the possibility of tilting and turning the duct fan. They confirm the silent operation of the device, sealed terminal box, motor protection against overloads. On the downside, it should be noted that the kit does not include a regulator for external speed control.

Advantages

high performance;
tilt and turn functions;
waterproof design;
motor overload protection.

Flaws

lack of external control.

Soler & Palau TD-350/125 SILENT

The Spanish duct fan Soler & Palau TD-350/125 SILENT is somewhat inferior in power to the rating winner. The model is ideal for small system ventilation in a private house. Its capacity is 360 cubic meters. m/h Experts consider the main advantage of the device to be silent operation (20 dB), the installation diameter is 125 mm. The case has reliable protection from moisture high-quality sound insulation does not allow the sound of the rotating blades to penetrate into living rooms. The model has 2 speeds, the rotation mode changes in steps.

Professional plumbing installers note the durability of the fan. Some products installed by them have been working without interruption for more than 8 years. Only a high price can be entered into a liability.

Advantages

silent operation;
quality assembly;
durability;
good protection from moisture.

Flaws

high price.

The Ukrainian inline fan VENTS TT PRO 200 is in the top three of the rating for an affordable price and excellent air exchange (1040 m3/h). Powerful engine(108 W) creates a high flow rate. The installation diameter of the device is 200 mm. The model has compact dimensions and low weight (3.95 kg). The waterproof design of the housing makes the device durable. The fan has two speed modes, which allows you to customize the ventilation system to your needs.

With all the positive qualities of the model, it also has significant disadvantage. During operation, the fan creates a loud howling sound (52 dB). It annoys many users, while they note the combination of affordable price and high performance.

Advantages

acceptable price;
waterproof case;
high intensity of air exchange;
compactness and lightness.

Flaws

loud howling sound.

The multizone device Soler&Palau OZEO-E is intended for the organization of the ventilation consisting of several shafts. The duct fan is designed for large private houses and commercial buildings. You can organize the hood from bathrooms and kitchens with a high level of humidity. The diameter of all nozzles is 125 mm. The manufacturer completes the model with three plugs, with which you can block the openings of the suction pipes. A modest performance (420 cubic meters / h) did not allow to take a place in the top three of the rating.

Users are satisfied with the work of the multi-channel Spanish fan, it does not create a lot of noise (38 dB) during operation. For ease of use, it is better to purchase an additional regulator from the same manufacturer.

Advantages

multichannel design;
waterproof design;
quiet work.

Flaws

modest performance.

The German duct fan Blauberg TURBO is available in six different versions. They differ in productivity (137-1750 cubic meters / h), and they are united by moisture-resistant performance and high-quality assembly. The body of the device is made of impact-resistant plastic, the diameter of the air ducts depends on the version (100-315 mm). Due to the special design, the motor-impeller unit can be removed without dismantling the entire device. two speed single phase motor has overload protection, the fan is controlled by a built-in switch. It is possible to connect an external regulator.

The model could not take a higher place in the ranking due to noise (47-56 dB). Stops potential buyers and price.

Advantages

wide choice of executions;
ease of maintenance;
two speed motor.

Flaws

noisy work;
high price.

For ventilation of rooms with different levels of humidity, the Bulgarian model MMotors VOK-T is suitable. But the main advantage of the fan, according to experts, is heat resistance. The body of the device and its impeller are made of aluminum alloy, some modifications are equipped with a fan made of heat-resistant polyamide. The maximum temperature is limited to 180°C. The electric motor runs quite quietly thanks to special ball bearings. The manufacturer guarantees up to 30,000 hours of trouble-free operation both when installed in a horizontal and vertical position.

Users in the reviews criticize the duct fan for low performance and limitation on the diameter of the duct. The model occupies the sixth line of the rating.

Advantages

metal case;
heat-resistant impeller;
low noise level.

Flaws

poor air exchange;
a small range of mounting diameters.

By itself affordable price implemented on Russian market duct fan Ballu FLOW 125. In addition to the attractive cost, experts note such an advantage of the device as a low noise level (30 dB). The compact model is designed to be built into a 119 mm diameter line. Due to the use of plastic, the manufacturer managed to create one of the lightest duct fans (1.5 kg). The device closes our rating, because in terms of the main parameters it loses to competitors. So, the intensity of air exchange is only 240 cubic meters. m/h, and from additional options only two-speed motor mode can be noted.

Users carefully examined the fan, finding in it weak sides. The main ones are the core and the stator of the motor. They get dirty over time, disabling the device.

Advantages

compactness and lightness;
low price;
low noise level.

Flaws

the internal components of the motor are not protected from dust and moisture.

Attention! This rating is subjective, is not an advertisement and does not serve as a purchase guide. Before buying, you need to consult with a specialist.

Deletion problem unpleasant odors stands in front of many residents of megacities. It is especially relevant in old houses with natural channels. As part of today's review, we will consider silent duct fans for exhaust hoods, analyze their types and advantages / disadvantages. Along the way, we will deal with those technical characteristics that you should definitely pay attention to, and tell you how to properly install such a fan and, if necessary, repair it. And we end our story with a review best models duct fans.

In the phrase of the title of the subsection, there are two terms that need to be parsed. These are "channel" and "exhaust". With the second, everything is easier. That is, the device must be installed on the exhaust section of the ventilation system. To make it clear what we are talking about, we explain that ventilation works on the principle of removing air masses and the same amount of inflow. One does not exist without the other.

Fans can be installed on or on an exhaust fan. Exhaust models are most often used. Incidentally, these devices are roof fans or centrifugal "snails" installed on the street.

The channel unit is a completely different design. It is cylindrical in shape, inside which a fan is mounted. That is, the device itself can become a continuation of the ventilation system duct or can be installed in the body of the wall, or rather in through hole made in the wall. More often, such models are called air, but no matter how they call it, the essence remains the same - air extraction with a fan.

Why is a silent fan better for a hood?

Now let's see why such fans are called silent. Any equipment that has rotating parts makes certain sounds associated with the formation of vibration. Fans have another reason to make noise - this is the air flow that passes through inner space device.

Attention! According to SNiP 23-03-2003:SN 2.2.4 / 2.1.8.562-96, the noise level inside residential premises should not exceed 35 dB. For comparison, there are several options for noise levels.

It is under the value of 35 dB that the noise level of the operating device is adjusted. This is achieved in several ways:

High-precision bearings are installed in the design of the fan, which are devoid of such properties as runout. No beat - no vibration of the motor shaft on which the fan impeller is mounted.
Precise balancing of the blades on the impeller creates conditions for the complete absence of vibration of the air flow.
Accurate selection of the number of blades, their angle of inclination.
Use inside the body of gaskets made of special rubber. In the process of down with operation, it does not burst and does not tear. Gaskets are installed between the fan housing and the legs (brackets) of the electric motor.

All this in a compartment creates conditions for silent operation of devices. Their noise level does not exceed 25 dB. That is why they got their name.

Varieties of duct fans

Basically silent or bathroom are divided into two categories:

in shape,
by design.

In the first case, there are two groups: with a round section of the body and with a rectangular one. In the second, these are axial fans, radial and centrifugal. Duct fans for round ducts are most often used in private housing construction. But there is one moment that determines the installation location.

For example, very often the exhaust section of a ventilation system is a vertical pipe (usually plastic or concrete) that permeates the building from the roof. They hide such an air duct in the walls during the construction process or build it in the form of a separate box. You can not install a duct fan in it. Because if the device fails, it will not be possible to repair or replace it. On such an air duct, you can put a roof model. Duct devices are mounted in air ducts that remain outside the building structures. For example, collected in the attic.

As for rectangular units, they can be attributed to the group of industrial exhaust fans. But this does not mean that they are not used in residential housing construction. Rectangular shape air ducts are also used in residential or office buildings. The photo below shows one of the models made of plastic. This is a wall or ceiling type device with a rectangular body. Pay attention to its blades, this is a centrifugal type fan. His blades are located along the direction of air flow.

Axial fans

An axial model or axial model is a device in which the direction of air movement corresponds to the location of the axis of the electric motor. An impeller is mounted on it. It is this design that has received great use in everyday life, because:

it has a low-power electric motor;
but this power is sufficient to provide the required air exchange both in living quarters and in office ones;
simple tube design.

Attention! By themselves, axial fans are the quietest among all models used.

Radial

The principle of operation of these devices differs from the previous ones in that the movement of air masses does not occur along the axis of the motor shaft, but with an inclination depending on the slope of the impeller blades. They can be tilted back or forward. Accordingly, with a forward slope, the fans are installed on the air supply, with a reverse slope on the exhaust.

But the slope affects not only the direction of the flow. There are other features as well:

Impeller shape	With forward curved blades	Curved back
efficiency	0,7	0,8
High pressure work	0,9	0,8
Working with air containing mechanical impurities	0,2	0,5
Explosion proof	0,6	0,5
Noiselessness	0,8	0,9
Controllability	0,2	0,1

Exhaust duct fans for the kitchen or bathroom are generally radial models.

Centrifugal

Centrifugal exhaust fan channel type is a novelty that has appeared on the market relatively recently. But she took her place firmly. A distinctive feature of this variety is the impeller with blades that are located longitudinally to the axis and do not have a slope in the longitudinal plane. They have a slope at the transverse plane.

The devices got their name only due to the fact that during the rotation of the impeller, the blades throw air towards the body of the apparatus, where a zone is formed. high blood pressure. And in the center, on the contrary, there is a zone of low pressure. That is, there is a sharp movement of air from the center. It is the pressure difference inside the housing that creates the conditions under which external air begins to be sucked into the unit.

And another one distinguishing feature- This is a special collector that performs the functions of a diffuser. Its design helps to facilitate the suction of air inside the fan.

Design and details of the duct fan

As mentioned above, the design of duct fans is a housing inside which an electric motor is installed. An impeller is attached to the shaft of the latter. The body has a cylindrical shape, but the length of the cylinder can be quite large relative to the diameter or not very large. The first includes models that are mounted on walls. To the second, which are installed in duct systems.

The first are supplied with two decorative ones, which are installed on the surfaces of the walls located on different sides. The latter are attached to the air ducts with special collectors on clamps, which are supplied with the fan. The latter are usually sold assembled.

Some models are equipped with non-return valves that do not release air when non-standard situations move in the opposite direction, that is, into the premises of the building. We must pay tribute to the fact that although the exhaust fan with a check valve is more expensive, but it protects interior spaces from improper operation of the ventilation system. For example, summer, heat, the fan "passed out" for some reason. If the temperature inside the house is lower than outside, then the air will begin to move in the opposite direction. check valve this will not happen.

Technical characteristics of duct fans and selection rules

Like all devices of this type, channel ones have one main characteristic: power (performance). More precisely, the volume of air that passes through the device per unit of time. Usually, cubic meters are used for measurement, passing in one hour - m³ / h.

This indicator depends on two parameters:

the speed of rotation of the electric motor (impeller), and the higher the speed, the higher the performance;
the overall dimensions of the fan itself, the larger they are, the greater the power.

In addition, it is necessary when choosing to pay attention to other qualities of the device. Namely:

Security class. This refers to protection against dust and moisture. This is especially important if .
Functionality. Here it is implied automatic operation device or standard. The second refers to the function when the device starts working when turned on. To the first, when it turns on at certain intervals programmed in the settings.

Fan performance

By eye, this option cannot be selected. Because it will depend on the required air exchange in the room. If we are talking about the general ventilation of the house, and not about a specific room, then you will have to add up the air exchange values \u200b\u200bof all the rooms of the house. This will be the performance of the fan.

For example, a house in which the total living area is 100 m², the ceiling height is 3 m. In them, the air exchange will be equal to the volume of the room, that is, 300 m³ / h. Here we must add the air exchange of the toilet and bathroom - 25 m / h each and the kitchen 60 ÷ 90, depending on the type and. It turns out:

300 + 25 + 25 + 70 = 420 m³/h.

This is the performance of the fan.

Geometric dimensions

The marking of fans of this type is based on the diameter of the inlet and outlet. Standard size for this parameter: 100 mm, 125, 160, 200, 250 and 315. Duct fan for exhaust 100 and 125 mm are classified as household. Inline fans 160 and 200 mm are more often installed in restaurants, cafes, shops large area and other institutions. The rest can be attributed to industrial models that are mounted in the air exhaust system. production shops. All of them are powered by 220 V electricity.

For example, let's analyze devices of the VKK brand (round duct fan), the photo and table below show its dimensional parameters.

How to install a duct fan

From the photo shown above, we can conclude that the device itself is selected according to the diameter of the duct. For example, if an exhaust fan with a diameter of 100 mm is installed in the system, then the air duct must also be of this size.

So, the installation begins with the disassembly of the device itself. It is necessary to unscrew the clamps and pull out the fan itself.
After that, the supply with two branch pipes, which are rigidly connected to each other, and more often they are a single part, is mounted in the air duct. That is, the nozzles are inserted into the two ends of the pipes, between which the fan is installed.
The stand or brackets are attached to the wall or ceiling, or to any other flat surface (columns, arches, etc.) piping. Fastening is made on dowels and self-tapping screws.
The fan is inserted into its place, attached to the nozzles with clamps, under which rubber gaskets are laid.

Attention! The distance from the elbow to the inlet pipe must not be less than one diameter. In the case of silent duct fans 100 mm, this distance should not be less than 10 cm. The distance from the outlet to the outlet or fitting should not be less than three diameters.

How to properly care

If we are talking about devices that are installed in the duct system, then maintenance is rarely carried out, especially if the pumped air is dry and clean. Once every two or three years, you can open it and clean it from dust. If possible, you can try lubricating the bearings. But, as practice shows, this is a matter for professionals.

With regard to wall-mounted fans, once a year it is recommended to remove the decorative grilles and clean the inside of the cylinder. Everything else is not available.

Do-it-yourself duct fan repair

Here's what is never recommended to do - do-it-yourself repairs. Typically, the fan motor or capacitor fails. If the first burned out, then it will have to be replaced with a new one. And it’s not a fact that you will find a motor in the store that matches the brand of the engine.

As for the capacitor, if you understand something in electrics, then you can handle the replacement. To do this, you will have to measure the capacitance of the part with a multimeter. If it corresponds to the passport (indicated on the case) or a little more, then it's not about him. But if the capacity is less, then you have to change. By the way, it is necessary to measure the parameter with the capacitor disconnected from the network with its preliminary discharge (close the two ends with a wire).

But, as practice shows, quality models will serve faithfully for more than a dozen years. And if at one point there was a failure in work, it is better to put a new one instead.

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