Hilti VC 20-UM Manual Original página 35

9 Troubleshooting
Fault
The audible warning
signal is emitted
(reduced suction power)
(VC 20‑UM/ VC 40‑UM).
Dust is blown out of the
appliance.
The appliance switches
itself off or on inadvert-
ently or the user receives
electric shocks (static dis-
charge).
The appliance doesn't
start or switches itself off
after a short time.
The motor doesn't restart.
Possible cause
The dust bag is full.
The filter element is clogged
with dirt or dust.
Blockage in the hose, vacuum
cleaner or power tool dust
hood.
The hose diameter and hose
diameter setting don't corres-
pond.
The filter element is not fitted
correctly.
The filter element is damaged.
The filter seal is damaged.
Electrostatic charge is not dis-
sipated correctly; the appli-
ance is connected to an un-
earthed/ungrounded power
outlet.
The water level cut-out is activ-
ated.
The mains circuit breaker has
been tripped.
The container is full.
The motor overheating protec-
tion cut-out has been activ-
ated.
The motor overheating protec-
tion cut-out switches the motor
off repeatedly as the ventilation
slots are clogged.
Remedy
Change the dust bag.
See section: 7.4.2 Changing
the plastic dust bag 4
See section: 7.4.1 Changing
the paper dust bag / filter
fleece
Change the filter element if ne-
cessary.
See section: 8.2 Changing the
filter element
Clean the hose and dust hood.
Set the switch to the correct
hose diameter setting.
See section: 7.1 Hose diameter
setting (VC 20‑UM/ VC 40‑UM)
Remove the filter element and
refit it correctly.
Fit a new filter element.
Fit a new filter element.
Connect the appliance to an
earthed/grounded power out-
let; use an antistatic hose.
Clean the probe and the area
around the probe with a brush.
Reset the circuit breaker. Find
the reason for the overload
current if it trips again.
Switch the appliance off.
Empty the container.
See section: 7.8.2 Emptying
the waste material container
when no dust bag is fitted
(collecting liquids)
Switch off the appliance and
allow it to cool for 5 min. If the
motor still doesn't start, con-
tact Hilti Service.
Clean the ventilation slots
carefully with a dry brush.
en
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