42 MALFUNCTION
7 MALFUNCTION
OBSERVATION
POSSIBLE CAUSE
SOLUTION
Ventilation unit runs at a higher
RPM than when first
commissioned.
LED indication lights up "2x
ORANGE" when the switch is
operated.
Ventilation unit goes to high
RPM – the desired flow is not
attained.
Filters dirty.
Air flow blocked. Thanks to
the constant flow control, the
RPM are automatically adapted
if obstructions limit the air
flow.
Clean filters.
Replace the filters and reset the
fault signal.
Check:
- whether all ducts are properly
connected.
- whether (during the construction
phase) any unwanted parts found
their way into the ventilation unit.
- that no sharp bends, flattened
ducts, etc. are present in the riser
pipes.
Filters service life has been
reached.
There is periodically a great deal
of exhaust and little supply of
the air.
The automatic frost protection is
active (defrost cycle of the unit).
This is the normal functioning of the
device, whereby the ventilation unit is
periodically heated with warm indoor
air. If this is not desired, you can
ventilate in balance by making use of
the optional electric preheater.
Siphon incorrectly connected.
Odour nuisance near the device.
Gurgling noises near the device.
Check the siphon and fill with water
if applicable.
Unwanted odours of fresh
supply air.
Suction inlet of ventilation unit is
too close to a used air discharge
outlet (range hood, chimney,
discharge outlet of ventilation
unit, etc.).
When installing, always pay atten-
tion that the suction inlet for fresh
air is located far enough away from
the used air discharge outlets.
If this is impossible, or you have
no control over the spreading of
unwanted odours, you can install
an activated charcoal filter in the
fresh air supply duct.
Condensation water coming out
of the ventilation unit.
The air ducts are not properly
connected.
For proper functioning, the supply
and discharge sides may not be
reversed. Check whether the
connections correspond to the
recommandations on p22-23.
The condensation drain is
not properly connected.
Make sure that the condensation
drain is properly connected.
The ventilation unit is not
hanging level.
Hang the ventilation unit level.
