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VTS reserves the right to implement changes without prior notice
Ventus Air Handling Units
- flexible connection (if any) is not damaged,
- all screws fastening construction elements of the fan unit are tight.
Lack of rotor's balance can be caused by:
- dust settlings on the rotor's blades,
- detachment of additional balancing weights,
- damage of the rotor's blades.
Checking the contamination level of the casing inside, rotor and motor should be carried out every
four months and the following elements should be cleaned:
- casing inside with a vacuum cleaner,
- rotor with a vacuum cleaner or by wet wiping with soft cleaning agent.
In order to achieve required life of the fan, it is necessary to check and clean the bearings regularly.
Fan bearings should be checked while carrying out other maintenance procedures.
Rotate with hands the fan's rotor to check if it rotates freely and correctly. If you can hear:
- silent sounds while rotating as a silent, soft and steady murmur - it means that the bearing
operates correctly,
- grinding noise - lubrication is required,
- harsh, often irregular noises, scrubbing or metallic, frequent noise - the bearing is damaged.
Please replace the bearing.
Check the bearing temperature with a thermometer or by touching the bearing's casing. If the
temperature is too high or if it changes violently, it means that the bearing does not work correctly.
A possible reason might be:
- lack or excess of grease,
- contamination, overload or damage of the bearing's balls,
- bearing clamping,
- excessive sealing friction,
- external heating
Temperature increase is a normal phenomenon during first 1-2 days after lubrication.
During appropriate operation bearings of direct driven fans do not need to be greased. Bearings of
fans with no casing with a belt drive are equipped with grease applicators. In this case bearings
should be greased with solid grease for bearings (table 13), in intervals characteristic of the AHU
operation intensity and current technical condition of the bearing. It is recommended to grease
once per each 9 months if the AHU operates in temperature not higher than 50
°
C, and in case of
higher temperatures every 4 months. Amount of grease depends on the fan size and applied
bearings. Excess of grease in the bearing casing results in increase of the bearing temperature,
especially in case of high rotation speed. After several greasing procedures, open the bearing
casing and remove old grease before applying the new one.
Table 15. Recommended greases for bearings
Manufacturer
Type
Base
Range of operation temperature (min/
max)
FINA
Marson HTL 3
Lithium
-30°C / +120°C
SHELL
Alvania Fett 3
Lithium
-20°C / + 130°C
ESSO
Beacon 3
Lithium
-20°C / + 130°C
MOBIL
Mobilux EP3
Lithium
-30°C / + 130°C
SKF
LGMT 2/S
Lithium
-30°C / + 110°C
