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VTS reserves the right to implement changes without prior notice
Ventus Air Handling Units
- the fan's rotor rotates freely and does not touch the stator,
- air cooling the motor can freely come in and out of the motor's casing,
- ground and protection connection are done correctly,
- the fan's designed rotary speed will not be exceeded (see AHU technical data),
- all screws, supporting elements and electric connections are fasten firmly,
- supply cables located inside the fan section are far from any loose drive elements and they are
fasten with appropriate clamps to the electric wiring,
- all dampers on the ventilation ducts network are set in accordance with the design,
- the rotor rotation direction is the same as a direction of the arrow placed on the fan's casing (switch
on the fan by pulsing). If they are arrange in different directions, change with each other any two
phases in the motor connection box or change rotation direction on the frequency converter,
- tension of the wedge-shaped belts and location of the pulleys is in line with the requirements of
point 7.5.3.
Once the aforementioned control activities are performed, close carefully all AHU's inspection
panels.
Operation of the device with open inspection panels is forbidden.
6. START-UP AND ADJUSTMENT
The start-up is going to test if the AHU is made in accordance with the design and is ready for
operation.
Start up and ventilation/air-conditioning systems adjustment can be done only by qualified and
competent start- up personnel, equipped with necessary test devices.
After completing activities described in point 5 you can proceed with the first start-up. In case of
AHUs equipped with secondary filtration section it is recommended to start up the system without the
secondary filter insert.
The fan should be started with lower load and lead towards parameters similar to the operational
ones. Lower load can be achieved by pushing the damper to on the AHU inlet and additionally, in
case of powering the motor through the frequency converter, by lowering the rotation speed.
During increasing the load, check all the time current consumed by the motor.
Always make sure that for designed air parameters current intensity powering the fan's
motor cannot exceed the rated value.
Ignoring recommendations concerning the first start-up can lead to motor's overload
and durable damage to the motor.
After start-up check if:
- there are no suspicious noises and unnatural mechanical sounds,
- there are no considerable AHU vibrations.
The AHU should operate for about 30 minutes. After that time turn it off and inspect individual
sections. Pay utmost attention to:
- filters (if they are not damaged),
- condensate drain-out,
- fan unit (belt tension, fans and motors' bearing temperature).
It is recommended to ensure a preliminary opening of damper on AHU inlet in the
automatics system before starting up the fan (standard of VTS automatics). It has some
impact on the damper durability and operation and eliminates activation of pressure
control.
After starting up the AHU replace or clean the preliminary filters.
Achieving required performance of the AHU depends, among the others, on carried out adjustment
