The supply fan (top) has stopped
Cause
Solution
a) The fan connector is loose or not properly connected.
●
Fit the fan connector on the correct connector
on the circuit board.
b) Frost control is active.
●
If the outside temperature becomes very cold,
the fan is switched off to avoid freezing of the
heat exchanger.
The fan will start running again when the
outside temperature rises enough.
c) The fan is blocked or stuck due to heavy soiling.
●
Clean the fan impeller. Watch out for the
balance clips.
d) The fan is defective.
●
Replace the fan.
e) The ventilation unit PCB is faulty.
●
Replace the PCB and carry out the
commissioning procedure again.
The ventilation unit is noisy
Cause
Solution
a) The fan is blocked or stuck due to heavy soiling.
●
Clean the fan impeller. Watch out for the
balance clips.
b) The fan is imbalanced.
●
Replace the fan.
c) The unit is mounted on a wall/ceiling/floor with
insufficient load-bearing capacity.
●
If the ventilation unit cannot be relocated, try
using vibration dampers to decouple it from
the wall, ceiling or floor.
d) The ducts are not correctly connected to the unit.
●
Check the connections and ensure that fixed
ducts are clamped to the wall, ceiling or floor.
e) The bypass valve is blocked (rattling noise).
●
The bypass valve strikes the stop during the
self-test after power is switched on. Wait 30
seconds and check whether the noise has
stopped.
●
Inspect the valve. Clean it if it has become
blocked with dirt. Replace the valve if there is a
different cause of the fault.
The ventilation unit is not responding to the RF remote controls
Cause
Solution
a) The battery of the RF remote control is empty.
●
Replace the battery.
b) The RF remote control is not paired with the
ventilation unit.
●
Restart the commissioning procedure and pair
the RF remote control.
c) The distance between the ventilation unit and the RF
remote control is too large or there are too many
obstacles interfering with the signal.
●
Try pairing the devices again. If this does not
work, move the RF remote control to a location
where there are fewer obstacles to interfere
with it.
d) The brand names of the RF control switch and the
ventilation unit are different.
●
Replace the RF device by one with the same
brand name as the ventilation unit.
e) The ventilation unit PCB is faulty.
●
Replace the PCB and carry out the
commissioning procedure again.
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