Replacing Fuses; Information On Cleaning - Viessmann VITOLIGNO 250-S Operating Instructions Manual

Maintenance
Heating system inspection and maintenance
Regular maintenance ensures trouble-free, energy effi-
cient and environmentally responsible heating. For
this, we strongly advise you to arrange an inspection
and maintenance contract with your heating contractor.
Boiler
Increased boiler contamination raises the flue gas tem-
perature and thereby increases energy losses. The
boiler must therefore be thoroughly cleaned by a heat-
ing contractor twice a year.
DHW cylinder (if installed)
Standards DIN 1988-8 and EN 806 specify that main-
tenance and cleaning should be carried out no later
than 2 years after commissioning and as required
thereafter.
Only a qualified heating contractor should clean the
inside of a DHW cylinder and the DHW connections.
If any water treatment equipment (e.g. a sluice or
injection system) is installed in the cold water supply of
the DHW cylinder, ensure this is recharged in good
time. For this, observe the manufacturer's instructions.
Safety valve (DHW cylinder)
The safety valve function should be checked by the
user or heating contractor every six months by venting
it. The valve seat may become contaminated (see the
valve manufacturer's instructions).
Drinking water filter (if installed)
For reasons of good hygiene:
■ Replace the filter element on non-backwashing filters
every 6 months (visual inspection every 2 months).
On backwashing filters, backwash every 2 months.
■

Replacing fuses

Danger
Contact with 'live' components of the control unit
can lead to fatal injury due to electric shock.
Only a heating contractor may replace fuses.

Information on cleaning

Danger
Contact with 'live' components can lead to fatal
injury due to electric shock.
Switch OFF the mains supply before starting
cleaning (e.g. at the mains isolator).
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Additionally, for DHW cylinders with sacrificial anode:
We recommend that the correct function of the sacrifi-
cial anode is checked annually by your heating con-
tractor. The function of the sacrificial anode can be
checked without interrupting system operation. The
heating contractor will check the earth current with an
anode tester.
Danger
Hot surfaces can cause burns.
Never touch hot surfaces inside the appliance or
on uninsulated pipes, fittings or flue pipes.