Troubleshooting - Hilti VC 20‑U Manual Original

will help to avoid distribution of the hazardous
dust deposited on it.
When maintenance or repairs are carried out, all
contaminated parts which cannot be satisfac-
torily cleaned must be packed in impermeable
en
bags and disposed of in compliance with the
applicable disposal regulations.
8.7 Maintenance
WARNING
Repairs to the electrical section of the ap-
pliance may be carried out only by trained
electrical specialists.

9 Troubleshooting

Fault
No suction / reduced suc-
tion performance.
Dust is blown out of the
appliance.
The appliance switches
itself off or on inadver-
tently 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.
14
Check all external parts of the appliance for
damage at regular intervals and check that all
controls operate faultlessly. Do not operate the
appliance if parts are damaged or when the
controls do not function faultlessly. If neces-
sary, the appliance should be repaired by Hilti
Service.
8.8 Checking the appliance after care and
maintenance
After carrying out cleaning and maintenance,
check that the vacuum cleaner has been cor-
rectly reassembled and that it operates fault-
lessly.
Test each of the functions.
Possible cause
The dust bag is full.
The filter element is clogged
with dirt or dust.
Blockage in the hose, vac-
uum cleaner or power tool dust
hood.
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 acti-
vated.
The mains circuit breaker has
been tripped.
Remedy
Change the dust bag.
See section: 7.2.2 Changing
the plastic dust bag 4
See section: 7.2.1 Chang-
ing the paper dust bag / filter
fleece
Change the filter element if
necessary.
See section: 8.2 Changing the
filter element
Clean the hose and dust hood.
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 sensors and the area
around the sensors.
Reset the circuit breaker. Find
the reason for the overload
current if it trips again.