9
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9
Special instructions
9.1.
Gas tightness
In gas-tight fans, the tightness must be regularly inspected in accordance with the actual level of risk. If the
health of humans is at risk and/or if permitted limit values are exceeded, the fan must be immediately shut
down.
Ensure that:
•
The room is always properly ventilated, so that, in the event of an undetected leak, no poisonous or
explosive gas concentration can occur
•
The shaft seal rings are not damaged during installation and maintenance work
•
The shaft surface is not damaged (i.e. by scratches, corrosion, etc.) near the seal rings
•
After reassembly of the unit, new sealing material is used and a leakage test is carried out
9.2.
Increased temperatures
For fans that are intended for conveying of hot media (tempera
tures >80°C), observe the
following:
•
Ensure that hot surfaces cannot be touched, by attaching insulation, protective grids, guards
and warning signs
•
In order to ensure that nominal motor power is not exceeded, close the outlet flap while the fan
is being cold-started
•
After the fan is switched off, ensure that the bearings and the bearing grease are not heated to
more than 120°C. If it is not possible to ensure this, the fan must be continuously operated until
the medium temperature is below 120°C. If the bearing temperatures are consistently too high
(>90°C) and cooling by means of cooling disks is not sufficient (due to low speeds), install an
external cooling system (external blower).
