13
Maintenance
Maintenance and Operation
1––Inspect the overall fan condition periodically.
Inspection intervals depend on fan operating conditions and may
vary from a minimum of 2 weeks to a maximum of 6 months.
The following components should be specifically inspected when
inspecting the overall fan conditions:
- Screw torque.
- Fasteners corrosion.
- General condition of blade surface.
2––Ice formation on the blades of operating fans must be strictly
avoided.
3––If ice has formed on a stationary fan, it must be removed prior
to start-up to avoid damaging the blades. Snow formed on a sta-
tionary fan must be periodically removed, according to the snow
accumulation itself.
4––Turn off 2-speed motor for at least 30 seconds before switching
to low speed.
5––Stop the unit completely before reversing the fan direction.
6––Check the vibrations level in the position shown in Figure 5 at
regular intervals.
The vibration level must not exceed the most restrictive amplitude
values between the limits imposed by the normative of the structure
where the fan is installed and the limits imposed by the VDI 2056
normative. In this case, shut down the unit and trace the cause of
such excessive vibration by referring to page 14.
It is advisable to keep a record of the readings taken on each oc-
casion for comparison. Always take readings at the same positions
and in the same manner. Observe the safety precautions insuring
power supply is turned off. The fan vibration levels constitute an
invaluable indication of the state of the plant and should be moni-
tored frequently (e.g. monthly).
Temperature Range
This series of fans are designed to operate at these temperatures.
Minimum is -20ºC (-4ºF)
Maximum is +82ºC (+180ºF)