Viessmann VITODENS 343-F WS4A Installation And Service Instructions Manual page 3

Safety instructions
Working on the system
When using gas as fuel, also close
the main gas shut-off valve and
safeguard against unauthorised
reopening.
Isolate the system from the power
supply and check that it is no longer
'live', e.g. by removing a separate
fuse or by means of a main isolator.
Safeguard the system against
unauthorised reconnection.
!
Please note
Electronic modules can be
damaged by electro-static dis-
charges.
Touch earthed objects, such as
heating or water pipes, to dis-
charge static loads.
(cont.)
Repair work
!
Ancillary components, spare and
wearing parts
!
Safety instructions
Please note
Repairing components which
fulfil a safety function can com-
promise the safe operation of
your heating system.
Replace faulty components
only with original Viessmann
spare parts.
Please note
Spare and wearing parts which
have not been tested together
with the heating system can
compromise its function. Instal-
ling non-authorised compo-
nents and non-approved
modifications/conversion can
compromise safety and may
invalidate our warranty.
For replacements, use only ori-
ginal spare parts from
Viessmann or those which are
approved by Viessmann.
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