Privacy Policy (GDPR)
Not registered yet? Take advantages of registration:
Products saving in a binding to the projects
Product consultation from our experts - Online
By using this form, you confirm that you have read the site terms of use Terms of use and completely accept the terms of use

VENTS TT Silent-M 355-4E

Inline mixed-flow fans in sound- and heat-insulated casing with the air flow up to 3310 m³/h.

  • Description
  • Characteristics
  • Capacity diagram
  • Downloads
  • Dimensions
  • Designation key
  • New inline VENTS TT Silent-M fans are enclosed in a specially designed sound-insulated casing that ensures silent fan operation in combination with high aerodynamic characteristics.
  • The fans are compatible with round air ducts from Ø 100 up to 450 mm. 
  • The VENTS TT Silent-M fans combine wide capabilities and high performance characteristics of both axial and centrifugal fans, thus providing powerful air stream and high pressure.
  • The VENTS TT Silent-M fans are recommended as a component of the air handling systems for various commercial and industrial premises with high requirements to noise level, i.e. in libraries, conference halls, educational institutions, kindergartens, etc.
  • The external casing is made of polymer-coated steel.
  • The inner casing perforation let sound waves pass through the holes and fall at a specific angle to the sound-absorbing layer.
  • The casing is internally heat- and the sound-insulated with 50 mm mineral wool layer.
  • The specially perforated casing and sound-absorbing material provide sound attenuation in a broad frequency band.
  • The inner casing and the impeller are made of high-quality durable plastic.
  • Due to the conic impeller and special blade profiling the circumferential air speed increases thus providing higher air pressure and capacity as compared to standard axial fans.
  • The diffuser, the specially profiled impeller and the directing vanes at outlet from the fan casing distribute air flow in such a way as to attain the best combination of high performance and high pressure at low noise level. 
  • The fan casing is equipped with an airtight terminal box for connection to power mains.
  • Single-phase energy efficient double-speed motor with low energy demand.

  • The motor is equipped with thermal switches for the motor overheating protection. 

  • The ball bearings extend the motor service life up to 40 000 hrs. at non-stop operation.
  • The motor has IP X4 ingress protection rating.
  • The double-speed motors are controlled with a built-in switch («V»option) or an external switch for multi-speed fans (available upon separate order).
TT Silent-M fan with a three-position speed switch
  • A built-in speed controller (P option), an external TRIAC or autotransformer speed controller (available upon separate order) enable smooth motor speed control when connected to the maximum speed terminal.
  • T option models are equipped with an adjustable turn-off delay timer, adjustable from 2 to 30 minutes.
TT Silent-M fan with a built-in speed controller
  • The fan may be mounted at any place and at any angle within the ductwork system.
  • Several fans may be installed in one system in parallel to attain higher air capacity or in series to increase operating pressure in the system.
  • The fan casing is equipped with fixing brackets for fastening to the floor, wall or ceiling.
  • The ideal solution for ventilation of the premises with high demands to permanent temperature control e.g. greenhouses.
  • The fan with the electronic temperature and speed control module provides automatic control of motor speed (air capacity) depending on the air temperature in the air duct or in the room.
The front panel of the electronic module has the following control knobs:  
  • speed control knob for setting the motor speed; 
  • thermostat control knob for setting the temperature set point; 
  • thermostat indicator light.
The fan is available in two modifications:  
  • with a temperature sensor integrated inside the fan air duct (U/U1 option);
  • with an external temperature sensor fixed on the cable, 4 m long (Un / U1n option).
  • Set the desired air temperature (set point of the thermostat) with the thermostat control knob. Set the required minimum impeller speed (air flow) with the speed control knob. The motor switches to maximum speed (maximum air flow) as the temperature reaches and exceeds the set temperature set point. 
  • The motor switches to the pre-set lower speed as the temperature drops down below the set temperature point. To avoid the frequent motor speed changes, e.g. when the temperature in the supply air duct is equal to the threshold value, the switching delay time is activated. 
There are two switch delay control logics for various cases: 
  • The temperature sensor-based switch delay (U option): the motor switches to higher speed as the air temperature exceeds 2°C above the set thermostat set point. The motor revers to the pre-set lower speed as the air temperature drops below the thermostat set point. This control logic is used to keep air temperature to within 2°C. In this case the motor speed switches are rare.
  • The timer-based switch delay (U1 option): as the air temperature exceeds the set thermostat set point, the motor switches to higher speed and the switch delay timer is activated for 5 minutes. The motor reverts to lower speed as the air temperature drops down below the thermostat set point and only after the delay timer countdown. This pattern is used for exact air temperature control. The speed switches for the fan with U1 option are more frequent as compared to the fan with U option, however the minimum operating cycle at one speed is 5 minutes.
Parameter TT Silent-M 355-4E
Measurement unit
Sound- and heat-insulated casing yes -
Phase 1 ˜
Voltage 230 V
Frequency 50/60 Hz
Fan power 578 W
Current 3.42 A
Maximum air capacity 3310 m³/h
RPM 1480 min-1
Max. transported air temperature 60 °С
Sound pressure level at 3 m Sound pressure level at 3 m 49 dBА
Protection rating IP X4 -
Duct diameter 355 mm
Number of poles 4 -
Casing material polymer coated steel -
Mass 35 kg
Duct for round air ducts -
Type supply and exhaust -
Mounting floor mounting, wall mounting, ceiling mounting, Inline -
Capacity diagram
Capacity diagram
  • Selection method:
  • Air flow:
  • Pressure:
Operating point
  • Air flow: --
  • Pressure: ---
Files archieve
Select document type
  • Advertising and printing products
  • Certificates
  • Technical documentation
"VENTS TT Silent-M" user's manual 05-2022 (V97EN-05) (pdf 3.83Mb)
"VENTS TT Silent-M" product description 09-2021 (pdf 1.48Mb)
Download image "VENTS TT Silent-M (ErP 2018)" for your website (png 380.07Kb)
Download high quality image "VENTS TT Silent-M (ErP 2018)" (psd 3.95Mb)
"TT-M, TT-MD, TT-MD EC, TT Silent-M, TT Silent-MD, TT Silent-MD EC" user's manual 06-2018 (V135EN-03) (pdf 3.41Mb)
"VENTS TT Silent-M 200" user's manual 01-2022 (V97-2EN-01) (pdf 3.18Mb)
VENTS TT Silent-M 355-4E
Parameter Value Measurement unit
∅D 353 mm
B 512 mm
B1 563 mm
H 538 mm
L 1069 mm
Designation key
Designation key
Series Air duct diameter Options
100; 125; 150; 160;
200; 250; 315
Т: off-delay timer adjustable from 2 to 30 minutes.
U: speed controller with an electronic thermostat and a temperature sensor integrated inside an air duct. Temperature-based operation logic.
Un: speed controller with an electronic thermostat and a temperature sensor fixed on a 4-meter cable. Temperature-based operation logic.
U1: speed controller with an electronic thermostat and a temperature sensor integrated inside an air duct. Timer-based operation logic.
U1n: speed controller with an electronic thermostat and a temperature sensor fixed on a 4-meter cable. Timer-based operation logic.
U2n: speed controller with an electronic thermostat and a temperature sensor fixed on a 4-meter cable. Temperature-based switching on/off.
R1: power cord with a mains plug.
V: three-position speed switch.
P: integrated smooth speed controller.
ErP data
Overall efficiency ƞ, (%)
Measurement category MC
Efficiency category EC
Efficiency grade N
Variable speed drive VSD
Power kW
Current А
Air flow m3/h
Static pressure Pa
Speed n/min-1
Specific ratio SR
Share your opinion

Please evaluate our updated site user friendliness