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3. Fan maintenance (once a year).
Even regular technical maintenance may not completely prevent dirt accumulation in the fans which reduces the fan capacity and
impairs supply air delivery into the premises.
Clean the fans with rugs or a soft brush. Do not use water, aggressive solvents or sharp objects as they may damage the impeller.
4. Condensate drain check (once a year).
The condensate drain (line) may get clogged by dirt and dust particles contained in the exhaust air. Check the drain line operation by
filling the drain pan under the unit with water, clean the U-trap and the drain line, if necessary.
5. Fresh air supply duct check (twice a year).
The supply duct grille may get clogged with leaves and other objects reducing the unit performance and supply air delivery. Check the
supply duct grill twice a year and clean it as required.
6. Duct system check (every 5 years).
Even regular fulfilling of all the prescribed above maintenance operations may not completely prevent dirt accumulation in the air ducts
which reduces the unit capacity. The air duct maintenance includes their periodic cleaning or replacement.
Fault
Possible reasons
Fault handling
The fan does not start
up during the unit
start-up.
No power supply.
Make sure that the unit is properly connected to
power mains and make any corrections, if necessary.
Motor is jammed, the impeller are
clogged.
Turn the unit off. Troubleshoot the motor jam and
the impeller clogging. Clean the blades. Restart the
unit.
Automatic switch
tripping following the
unit turning on.
Overcurrent resulted from short circuit
in the electric circuit.
Turn the unit off. Contact the service centre.
Low air flow.
Low set fan speed.
Set higher speed.
The filters, the fans or the heat
exchanger are dirty.
Clean or replace the filter, clean the fans and the
heat exchanger.
The ventilation system components (air
ducts, diffusers, louver shutters, grilles)
are clogged or damaged.
Clean or replace the ventilation system
components, such as air ducts, diffusers, louver
shutters, grilles.
Low supply air
temperature.
The extract filter is soiled.
Clean or replace the extract filter.
The heat exchanger is frozen.
Check the heat exchanger condition. Turn the unit
off and restart it after the freeze danger is no longer
imminent.
High noise, vibration.
The impeller(s) are soiled.
Clean the impeller(s)
The fan or casing screw connection is
too loose.
Tighten the fan or casing screw connection against
stop.
No anti-vibration dampers.
Install anti-vibration rubber mounts.
Water leakage.
The drain pipe is clogged, damaged or
wrong mounted.
Clean the drain line, if necessary. Check the drain
line slant, inspect the U-trap and make sure the
drain line is equipped with frost protection.
Possible faults and troubleshooting
TROUBLESHOOTING
STORAGE AND TRANSPORTATION RULES
Store the unit in the manufacturer’s original packing box in a dry ventilated premise at the temperatures from +5 °C up to +40 °C and
relative humidity up to 80%.
Storage environment must not contain aggressive vapours and chemical mixtures provoking corrosion, insulation and sealing
deformation.
Use hoist machinery for handling and storage operations to prevent the unit damage.
Fulfil the handling requirements applicable for the applicable freight type.
Transportation with any vehicle type is allowed provided that the unit is protected against mechanical and weather damage.
Avoid any mechanical shocks and strokes during handling operations.
