Centrifugal fans

The state-of-the-art high-rise construction demands mechanical and energy-saving ventilation. Mono-pipe ventilation system that enables air exhaust from several premises through a single ventilation shaft is the most common solution for such application. Several flats can be connected to one ventilation shaft. Correct ventilation arrangement is of special importance for flat reconstruction and rearrangements.

The flexible ventilation system is the ideal solution just for such cases. It is designed at the construction stage and meets a number of important requirements such as fire safety, minimum mounting space, modern design, simple functions and operation modes of the fans for maximum comfort in the apartment. VENTS VN fans fully meet these requirements as they combine maximum operating efficiency and absolute fire safety (modification in fireproof casing).

Ventilation arrangement in residential houses with mono-pipe system

Fresh air intake
Fresh intake air from outside is supplied free of dust with low noise level through intake devices such as window or wall vent to bedrooms and living quarters. The vents are suitable for wall- and window installation and provide air flow regulation.

Extract air removal
The extract air from living premises is removed through kitchen, toilet, bathroom and other non-residential premises into the common exhaust ventilation system by high-efficient VN fans

Fire prevention
To prevent penetration of fire and smoke through the ventilation system air
ducts in case of fire the following solutions are used:

1. Fireproof casing
   High fire-retarding characteristics of the casing allow using the fan to meet the increased fire-prevention requirements for high-rise residential construction. Fire resistance rating is E90/160.
2. Fire damper
   Installed in the ducts laid out through fireproof walls and ceilings. The damper fire resistance rating is ЕIS 120.

Hygienic standards demand forced mechanical ventilation of bathrooms and toilets in the flats, hotels and other buildings (see the table). A mono-pipe ventilation system based on VENTS VN fans has convincing advantages as compared to other exhaust ventilation solutions.

The VENTS VN fans combine a number of unique features:

• the fan maintains permanent high pressure level and changes the turbine rotation speed automatically as a function of the resistance level in the system;
• special accessories make the VENTS VN fan a completely fire-proof unit recommended for use in high-rise construction;
• fan speed switching system allow selecting the best operation mode while installment;
• the fan is suitable for continuous non-stop operation. The automatic switch to increased capacity mode is provided;
• due to low noise level (~ only 26 dBA at the lowest speed) this fan type is considered the quietest one within its model range.

The VN fans maintain high pressure in the duct systems due to increasing the rotation speed depending on the resistance fluctuation in the system and keep the constant air flow rate while:

• synchronous operation of many fans integrated into one ventilation system;
• maximum load on the assembled air duct;
• insufficient air intake;
• high resistance of the roof hood.

Well balanced turbine, intellectual casing design and automatic operation mode selection ensure low-noise operation of the VN fans.

Components description VN fans

Fans for wall flush mounting

VNV-1 80 KP — fan in fireproof casing

VNV-1 80 KV — fan in plastic casing

VNV-1 80 KVK — fan in plastic casing with fire-retarding damper

Fans for wall surface mounting

VN-1 80 — fan in plastic casing

VN-1 80 K — fan in plastic casing with fire-retarding damper

VN 80 — fan in plastic casing

VN 80 K —fan in plastic casing with fire-retarding damper

1. Front panel
The compact design and easy mounting makes the fan match well with any room interior. Removable panel provides easy access to the filter.

2. Grille
The ornamental grille serves as a front panel of the fan. The grille design enables easy access to the filter elements and internal part of the fan.

3. Filter
For protection of the motor, impeller and the assembled air duct from penetration of dust and dirt carried with the air. The filtering element is made from polyether (A) for G4 purification class or from polyurethane foam (B) for G3 purification class.

4. Scroll casing
Made of durable ABS plastic. The unique design provides attaining the best aerodynamic characteristics during the fan operation. The fan is easily mounted into the casing by means of latches.

5. Motor
The design of two or three speed motor with ball bearings developed in compliance with our requirements by Company, the worldwide leading fan and motor manufacturer, ensures reliability and durability of our products. The fan can automatically switch to the required capacity level depending on the system resistance. Automatic selection of the best operation mode let save energy considerably. The impeller has forward curved baldes and is dynamically balanced for precise characteristics, low noise level and safe operation while assembly.

6. Plastic casing for flush mounting to wall
Installed into a wall during general construction works. The casing is made of high-quality durable ABS plastic. It is equipped with a backdraft damper and has additional flanges for connection to branch pipes for adjacent room ventilation.

7. Plastic casing for wall surface mounting
Made of high-quality durable ABS plastic and equipped with a backdraft damper.

8. Airtight backdraft damper
The backdraft damper is incorporated into the plastic casing to disable air back draft from the main shaft into premises when the fan is not
running. During the fan operation air is exhausted directly into the main shaft.

9. Fireproof casing for flush mounting to wall
Designed to prevent penetration of flame products into the premises in case of fire. Made of silicate plates manufactured by special calcium silicate technology. The plates contain no asbestos and have high mechanical and insulation properties. High hygroscopic and vapor permeable features provide humidity regulation by the material itself. High fire-resisting characteristics of the casing let the fan meet the increased fire safety requirements and enable the fan use for high-rise construction.

10. Fire-retarding damper
Serves to prevent fire and smoke penetration along the air ducts. As the temperature in the shaft reaches 90°С the thermal fuse melts and the damper shuts automatically hot air access off. This way the flame and smoke penetration though the ventilation shaft system is prevented. The damper plate is made of stainless steel. The fire-retarding damper serves as a backdraft damper when the fan is off and prevents air moving from the ventilation shaft.

Options for 2 speed fan models

T — timer modification:
The fan is switched on to the maximum speed manually with the external switch, turn-on delay time is 50 seconds. The return to default position is performed with the timer, run-out time is 6 minutes. Continuous low speed operation is possible.

TR — adjustable timer modification:
The fan can be switched to the maximum speed manually with the external switch. Turn-on delay time is set with the internal regulator ranging from 0 to 150 seconds. Run-out time is set with the internal regulator from 2 to 30 minutes. Continuous low speed operation is possible.

I — interval switch modification:
The fan switches periodically to the maximum speed while operation.The switching interval is set by means of the internal regulator ranging between 0.5 and 15 hours. Run-out time is 10 minutes. The fan can be switched manually with the external switch, turn-on delay time is 50 seconds. Continuous low speed operation is possible.

F — built-in photosensor modification:
The fan switches to the maximum speed after turning-on the light in the room, turn-on delay time is 50 seconds. After decrease of illumination level below the set threshold the fan switches to the runout operation mode with the duration from 2 to 30 minutes set by the internal regulator. Continuous low speed operation is possible.

H — humidity sensor modification:
The fan switches to the maximum speed as relative humidity level in the room increases. It switches off as relative humidity level drops by 10 % below the set level. The humidity threshold is adjusted in the range between 60 % and 90 %. Force switching to the maximum speed is provided, in this case the turn-on delay time is 50 seconds, and the run-out time is set by the internal regulator between 2 and 30 minutes. Continuous low speed operation is possible.

Air shaft calculation in multi-storey buildings

The charts below show the ventilation shaft size as a function of number of storeys in the multi-storey buildings with mono-pipe ventilation system.

Ventilation system arrangement example

Air exchange arrangement requires special attention in modern residential construction. Lack of ventilation caused by airtight windows cannot be solved with old technical means because of no slots for air intake in such windows. Whatever the cross section of the kitchen or bathroom exhaust vent may be, air flow is not possible without arranged supply ventilation from outside.

Exhaust ventilation of a multi-storey residential building can be arranged as follows. Mechanical exhaust ventilation systems with natural air intake are designed with exhaust fans in a kitchen, bathroom and toilet. The window or wall vents provide air intake from outside. Fresh air is supplied to bedrooms, living rooms and other residential rooms. After air exchange extract air moves through the inner doors to a bathroom, toilet and kitchen, where it is removed by exhaust fans.

1. VNV fan for wall flush mounting in fireproof casing
2. VNV fan for wall flush mounting in plastic casing
3. VN fan for wall surface mounting
4. Roof fan VKH (VKV)
5. Wall grille MV
6. Wall vent PS 100, PS 101, PS 102
7. Door ventilation grille MV 430/2, MV 450/2
8. Window vent PO 400
9. Spirovent air ducts
10. Aluvent (Thermovent) air ducts
11. Fire damper PL 10