Forced ventilation using fans is needed where there is no good natural draft. The selected model of the fan must correspond in terms of power to the volume of the room and its purpose. Most often, fans are installed in blind rooms without windows: toilets and bathrooms.
Why do you need an exhaust fan
In many apartment buildings, for various reasons, natural ventilation does not work. Most affected are rooms with high humidity or the release of heat and odors: kitchens and bathrooms. Here condensation settles on the glass and tile, mold appears in the corners, and unpleasant odors spread into the living rooms.
A fan for ventilation of the apartment will save the situation. It will draw out moist exhaust air and create the necessary air exchange. To make the appearance of a fan in the ventilation system really useful, the device is selected for a specific room according to certain parameters. Too powerful, it will cause drafts, completely unacceptable for the bathroom. A weak fan will not cope with its function, in vain using the master kilowatts.
Types of fans
There are several types of fans for ventilation of household premises for various purposes on the market.
Structurally, they are divided into three types:
- Axial;
- Centrifugal;
- Channel.
Axial fans - This is exactly the type that is installed in apartments. Axial fans for exhaust ventilation work very efficiently, are easy to install, and therefore are suitable for rooms of any purpose.
Centrifugal fans commonly used in large industrial plant systems and for tunnel ventilation. Centrifugal fans are called “snails” for the similarity of the shell to the gastropod shell. They are quite bulky, so their installation in the apartment is difficult. But some manufacturers create compact household models for bathrooms. This type of equipment is 2.5 to 3 times more expensive than the previous one, but the fan performance for ventilation is several times higher at the same power.
The intensity of the fan in the ventilation system depends on the size and shape of the blades. Centrifugal fans create high pressure, reduce losses during the movement of air through winding networks and even during elevations.
Duct fans for forced ventilation are installed directly in the duct. There are models for round and rectangular sections. In addition to the main function, duct fans are equipped with humidity and shutdown sensors. Such devices are started when the specified humidity level in the room is reached and stopped automatically. Duct exhaust fans are often hidden in a waterproof housing. Therefore, they can be installed in saunas, indoor pools, conservatories and other wet places.
At the installation site, household fans distinguish:
- for a bathroom;
- kitchen
- for bathrooms;
- window;
- ceiling;
- high temperature.
Household fans with a non-return valve designed specifically for ventilation of kitchens and bathrooms of apartment buildings. The valve does not allow the exhaust air to return from the exhaust duct to the apartment.Irresponsible residents of the houses independently insert fans to ventilate the bathroom or kitchen into the central exhaust duct, causing its depressurization. Exhaust air from the kitchen or toilet is distributed in neighboring apartments. Therefore, in the kitchen and in the bathroom, it is advisable to install a fan with a check valve.
Household fans with ventilation grilles have a capacity of not more than 3 thousand cubic meters of air per hour and are built into the channels of not more than 400 mm in diameter.
In residential buildings, wall fans are usually used, since the exits from the ventilation ducts are located in the walls.
Silent fans can not be called a separate category, but it is precisely for this indicator that home appliances are often selected. The silent fan for ventilation is ideal for small apartments. Quiet operation is provided by a special form of the blades and their slower movement. Most often, silent axial fans get for household exhaust ventilation.
High temperature fans are installed in saunas, steam rooms, fireplace rooms to eliminate steam and smoke from the room. Equipment of this class can withstand temperatures of 70 - 180 degrees Celsius. When purchasing a fan for forced ventilation of the sauna, it is advisable to select a model with additional protection against moisture from entering electrical parts (IP class protection).
In addition to the above, there are also corrosion-resistant, intrinsically safe, for smoke removal, dust and jet fans for ventilation of tunnels. These are powerful and dimensional devices used in industrial systems. We dwell in detail only on household models.
Criteria for choosing a fan for forced ventilation
Performance - This is the main indicator that pays attention when choosing a fan for ventilation of the apartment. Fan performance is calculated using the following formula:
P = Kv * O,
Where Sq - this is the multiplicity of exchange for a given room,ABOUT - the volume of the room.
The rate of air exchange depends on the purpose of the room, this is a constant indicator, which is indicated in SNiP.
An additional 10 - 15% error is added to the resulting figure.
Noise level It is very important when choosing a fan for ventilation of a small apartment. During operation, any type of fan generates two types of noise: aerodynamic and mechanical. Mechanical noise occurs when the body vibrates, the friction of the blades or the rattling of loose parts. Aerodynamic noise occurs when air moves through the ducts and between the fan blades. The noise level of a fan operating in a residential area must not exceed 25 decibels. For the kitchen, appliances that reproduce up to 35 decibels are purchased. Fans for ventilation of the bathroom and toilet can work a little louder, because they turn on for a short period of time. Noise characteristics are indicated in the documentation for the device.
To reduce noise, an insulating box and a silencer are installed. But this option is used in industrial fan systems for ventilation of tunnels.
Degree of moisture resistance - An important point when choosing a fan for the bathroom, sauna and ventilation of other rooms with difficult climatic conditions. Any fan works from electric traction, so it is necessary to protect the contacts from moisture and steam. Otherwise, there will be a short circuit and even a fire. 24 V fans are less dangerous.
Degree of heat resistance - is taken into account when buying a fan for ventilation of rooms with fireplaces, steam rooms and baths. The fan casing must withstand high temperatures, therefore it is made of metal.
Ease of use not the last parameter when choosing a fan with a ventilation grill. You can purchase an electric fan for ventilation of any room that will turn on with the light. This method leads to unnecessary expenses. So, after bathing in the bathroom it is always very humid. To drive out the raw air, you will have to leave both the light and the fan on.
Fans equipped with humidity sensors or timers are more practical for home ventilation systems. The sensor starts the engine regardless of lighting and the presence of people in the room, and the timer turns it off after a set period of time.
Value for money. A powerful and quiet fan for the ventilation system of an apartment can break down without working for a year. Therefore, pay attention to the products of large and well-known manufacturers. They are supplied with quality certificates, warranty, special markings that determine the protection of the product. Minimum protection class IP 34.
Do not rely solely on fan sizes. A very powerful device can be hidden in a small case. And even the price does not always mean high quality. A solid domestic device will work for at least 5 years.
The choice of exhaust fan, depending on the purpose
For bathroom and toilet Household overhead wall fans are perfect. They cope with small areas, while saving energy. Such a device is very easy to install. Part of its body is inserted into the ventilation duct, another protrudes and is covered by a ventilation grill.
The built-in hydraulic sensor will increase the efficiency. He will turn on the engine when the humidity in the room rises and independently turns it off. It is desirable that the fan for the bathroom has increased moisture protection. Fan performance for bathroom ventilation - 60 - 350 cubic meters per hour, depending on the size of the room.
Window fans installed in a window or in a hole in the wall. Such fans are more often installed in shops, hairdressers, in warehouses, in cafes.
To install a window fan, it is necessary to make a hole in the glass, so installing them in installed plastic windows is problematic. If desired, you can embed the fan in the double-glazed window even at the stage of its assembly.
The instructions for the fan indicate the maximum permissible thickness of the glass. There are supply and exhaust window fans with a round or square profile. The round ones are often equipped with a check valve, it prevents street dust from entering the room.
Most models are silent, regardless of power, the best models produce no more than 46 decibels. The performance of window fans for ventilation reaches 1 thousand cubic meters per hour.
There are models with remote control. Window fans are economical and inconspicuous in the interior.
Kitchen fans installed directly in the exhaust hood. Choosing a fan for ventilation of the kitchen, it is necessary to clarify the degree of heat resistance. To protect the fan blades from grease and soot, a protective net is installed on the side of the room. A container is provided for collecting grease and dirt. The axial fan for ventilation of the kitchen should be collapsible, this will simplify its cleaning. Most models have several power levels.
After watching the video, you can correctly install the purchased fan:
