dry brush. Clean the outside of the appliance at regular
intervals with a cloth. Do not use a spray, high-pressure
water-jet system, steam pressure cleaning equipment or
running water for cleaning. This may negatively affect the
electrical safety of the appliance. Always keep the grip
surfaces of the appliance free from oil and grease. Do not
use cleaning agents which contain silicone.
For vacuum cleaners of the class M, please note: The
en
appliance must be handled for cleaning and maintenance
in a way that avoids exposing maintenance personnel
and other persons to any hazards. Use filtered forced
ventilation. Wear personal protective equipment. Clean
the maintenance area in a way that prevents hazardous
substances escaping into the surrounding environment.
Vacuum off the outer surfaces of the appliance, wipe it
clean or seal it in suitable container or material before
removing it from an area contaminated with hazardous
substances. This will help to avoid distribution of the
hazardous dust deposited on it.
When maintenance or repairs are carried out, all con-
taminated parts which cannot be satisfactorily cleaned
must be packed in impermeable bags and disposed of in
compliance with the applicable disposal regulations.
A vacuum cleaner of the class M must be subjected to a
technical inspection by Hilti Service or a trained person
at least once a year to check, for example, for damage to
the filter, air leakage, and to ensure correct operation of
controlling devices.
8.5 Care of the Li-ion battery
Avoid ingress of moisture.
Charge the battery fully before using it for the first time.
In order to achieve maximum battery life, stop discharging
the battery as soon as a significant drop in performance
is noticed.
NOTE
If use of the tool continues, further battery discharge will
be stopped automatically before the battery cells suffer
damage. The tool switches itself off.
9 Troubleshooting
DANGER
In the event of a malfunction, disconnect the supply cord plug from the power outlet. Remove any batteries from the
battery compartment. The malfunction must be remedied before further use of the appliance.
9.1 Battery and mains-powered operation
Fault
The warning tone is activated
(reduced suction performance;
VC 20‑UM‑Y/ VC 40‑UM‑Y).
34
Printed: 28.03.2019 | Doc-Nr: PUB / 5140202 / 000 / 04
Charge the battery with the Hilti charger approved for use
with Li-ion batteries.
NOTE
- A conditioning charge (as is required with NiCd batter-
- Interruption of the charging procedure has no negative
- Charging can be started at any time with no negative
- For best results, batteries should be stored fully
- If the battery no longer reaches full charge, it may
8.6 Maintenance
WARNING
Repairs to the electrical section of the appliance may
be carried out only by trained electrical specialists.
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 necessary, the appliance should be repaired by Hilti
Service.
8.7 Checking the appliance after care and
After carrying out cleaning and maintenance, check that
the vacuum cleaner has been correctly reassembled and
that it operates faultlessly.
Test each of the functions.
Possible cause
The dust bag is full.
ies) is not necessary.
effect on battery life.
effect on battery life. There is no memory effect (as
with NiCd batteries).
charged in a cool dry place. Storing the battery in
places subject to high ambient temperatures (e.g. at
a window) has an adverse effect on battery life and
increases the rate of self-discharge.
have lost capacity due to aging or overstressing. It
is possible to continue working with a battery in this
condition but it should be replaced in good time.
maintenance
Remedy
Change the dust bag.
See section: 7.5.3 Changing the
plastic dust bag 4
See section: 7.5.2 Changing the pa-
per dust bag 2