Roof fan for hood - application, device, how to choose

Fans appeared in our everyday life for a very long time and since that time they have been more and more improved and modified. The meaning of this device is high-quality ventilation of air in the room. But what is it for?

Stagnant, waterlogged and dusty air is harmful to the human body. The exhaust fan is simply irreplaceable in those rooms where excess moisture, odors or smoke accumulates. Therefore, high-quality air extraction is needed in almost every building. Today we are going to talk about roof fans.

Roof fan for exhaust

This type of climatic equipment is mounted directly on the roof of buildings. How does it work and what are its main tasks?

The main functions of the roof fan:

• elimination of moisture;
• foreign odors;
• smoke;
• gases;
• prevention of mold and mildew.

The device effectively cleans the air in industrial, commercial, office, private and other premises. It provides not only clean air, but also fire safety by preventing or removing smoke from the air. The device can work continuously or turn on at the time of emergency.

Where are roof exhaust fans used?

These universal devices are used everywhere in ventilation systems: in shops, production areas, fitness centers, offices, cottages, warehouses, garages and catering establishments. In private buildings, they are necessary in halls where fireplaces are installed, in the dining room and sanitary zone.

Device

All devices, regardless of the many varieties, consist of 4 main parts: engine, casing, confuser and base.

They are necessarily equipped with an automatic regulator. As additional parts can be used: deflector, temperature sensors and others. The principle of operation depends on the design of the impellers of the device.

Types and differences

There are several main types of exhaust fans: axial, centrifugal, radial and diagonal. Each of them has its own characteristics, strengths and weaknesses. Models may also differ in size, performance, power and other characteristics.

There are special devices used in places with open fire, in explosive conditions.

Axle wheel systems

This is a duct device that transports air along an axis. Suitable for short air ducts. It is located in the exhaust duct and carries out air intake and delivery at the same time. Typically, these machines are equipped with backward-curved blades, which increases their productivity. Typically, the efficiency of such devices is low, and the noise produced is 30–40 dB. They are used without air ducts mainly for industrial and office buildings.

• Cons: can only be used in one-story buildings.
• Pros: easy installation, ease of use, high efficiency, reliability.

Radial systems

The instrument wheel consists of an impeller with blades turned forward or backward. If they are made of anti-corrosive material, the device is capable of working in aggressive environments. The system is effective for smoke extraction. The air flow is projected at an angle of 90 degrees to the wheel's axis of rotation. The efficiency of this type is higher than the axial ones, they are more powerful.

They work even in strong wind conditions. Equipped with a protective cap against atmospheric precipitation. The motor is 2 or 3 speed, which is convenient for adjusting performance in different conditions. Some models allow you to reduce the power consumption of the device by adjusting the motor speed.

Diagonal systems

The intake of air masses in such systems occurs axially, but the discharge is carried out diagonally due to the special shape of the impeller blades.

Centrifugal system

It differs from others in the use of centrifugal force. The devices release air at an angle of 90 degrees to the axis of the ventilation duct. It functions well even in windy conditions.

• Cons: cannot be used in houses and cottages, makes a lot of noise, is not able to work with aggressive environments.
• Pros: high performance, the ability to use in multi-storey buildings.

How to choose a roof fan for the hood

Before purchasing equipment, consider where and what it will be used for. After all, the effectiveness of its functioning depends on how correctly the type of device is chosen, as well as competent installation.

When choosing a roof fan, you need to consider:

• number of storeys of the building;
• the volume of the expected load;
• place of installation;
• device power and performance;
• terms of Use;
• functionality;
• noise level;
• availability of protection against aggressive environment;
• manufacturer and reviews.

The cost of industrial-type units and those used for private buildings differs tenfold. Choose models without overpaying for extra features and power.

Basic rules for installing roof exhaust fans

A significant advantage of such fans is their installation on the roof, outdoors. This helps to save usable floor space and does not disrupt the design. At the same time, air ducts are absent or their length is insignificant.

Installation rules:

• Prepare a solid base and hole.
• Preliminary waterproofing of a concrete or brick base.
• Installation of a glass.
• Placement of a vertical fan with a valve in it.
• Installation of special insulated deflectors at the outlet to protect against snow.
• Sealing gaps and edges with sealant. It is possible to make a cement screed and waterproofing.

We advise you to entrust the installation of ventilation equipment to a specialist, since the efficiency of its work will depend on the quality.

This climatic equipment is necessary to maintain a healthy indoor climate, prevent air stagnation and fire safety. Clean air is the key to good health and longevity.