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The following warning pictogram is located on the panel:
Rotating parts
6.12 - Plate heat exchanger
Check the plate heat exchanger once a year for
contamina-tion and if necessary clean with compressed air
against the direction of the air flow. If dampers are used,
follow the instructions in section 6.6.
Check condensate pan for contamination and clean if
necessary.
Check the droplet eliminator fins in the condensate pan (if
installed).
6.13 - Recirculation damper
For maintenance of this damper refer to chapter 6.6.
6.14 - Fan
6.14.1 - General
• CAUTION: The air flow may cause stationary
parts to move (even a fan that is switched off)!
• CAUTION: While working on the fan, the switch
has to be locked open.
Before switching off the fan always check if an electric
heater is installed. If this is the case, the electric heater
must always be switched off first. The fan must continue to
run for at least five minutes to cool down the heater coils.
• The data for belt type, belt tension, number of belts,
size and type of pulley is indicated on the fan housing.
6.14.2 - Bearings
The bearings of the smaller fan types cannot be lubricated.
If the larger fans are of the re-lubricated type, they should
be lubricated every six months. For higher temperatures
and increased contamination the lubrication interval should
be adjusted as required. For higher temperatures and a
higher degree of humidity use a lubricant recommended by
the supplier.
The electric motors are equipped with roller bearings.
Depending on the motor size the bearings are lubricated
for life or equipped with a grease nipple. The lubrication
interval and type of lubricant are as above.
It is recommended to check the motor and fan bearings for
excessive vibration. This can be a sign of bearing wear, but
also of incorrect operation of the transmission or an
unbalanced system.
The following points require extra attention:
• Check for vibration.
• Check the rotation direction.
• Avoid unnecessary stops and rapid start-ups of the
fan.
If the fan speed changes or if a motor with different power
specifications and/or speed is installed, this must be
discussed in advance with the manufacturer. The supplier
must re- calculate the bearing load as well as the impeller
load. If this is not done, irreparable damage to the fan may
incur. The supplier does not accept any responsibility for
modifications that have not been approved. See chapter
1.1.
CAUTION: While working on the fan the switch has to
be locked open.
The warning pictograms indicating rotating parts, electrical
voltage and opening of doors are attached to the door.
After changing the motor, transmission or frequency
converter settings:
• Check the fan rotation direction.
• Check the power input.
CAUTION: While working on the fan the switch has to
be locked open.
6.14.3 - Transmission
After starting up the unit and after replacing the belts, the
belt tension must be checked within one week and then
after two weeks, and further tensioned if required. After that
check the belt tension and inspect the condition of the belts
every three months.
The CORRECT BELT TENSION depends on:
•
the belt type
•
number of belts
• smallest pulley diameter
• power to be transmitted
• belt velocity.
The belt tension is calculated for each transmission. If the
belt tension is too high this can result in bearing wear and
vibration, if it is too low this can result in belt slippage and
pulley and belt wear.
Sequence for installation of new belts:
• Ensure that the pulleys are correctly aligned. If
necessary re-align.
• Position all belts loosely on the pulleys, do not pull
tensioned belts over the pulleys.
•
Tension the belts and check the tension with a Sonic
Tension Meter.
• Re-check the alignment.
