3
Working on the system
■
Isolate the system from the power sup-
ply (e.g. at a separate MCB/fuse or a
mains isolator) and check that it is no
longer 'live'.
Note
In addition to the control circuit there
may be several power circuits.
Danger
Contact with live components can
result in severe injuries. Some
components on PCBs remain live
even after the power supply has
been switched off.
Prior to removing covers from the
appliances, wait at least 4 minutes
until the voltage has completely
dropped out.
■
Safeguard the system against recon-
nection.
!
Please note
Electronic assemblies can be dam-
aged by electrostatic discharge.
Prior to commencing any work,
touch earthed objects such as heat-
ing or water pipes to discharge
static loads.
Repair work
!
Please note
Repairing components that fulfil a
safety function can compromise the
safe operation of the system.
Replace faulty components only
with genuine Viessmann spare
parts.
Auxiliary components, spare and wearing parts
!
Please note
Spare and wearing parts that have
not been tested together with the
system can compromise its func-
tion. Installing non-authorised com-
ponents and making non-approved
modifications or conversions can
compromise safety and may invalid-
ate our warranty.
For replacement, use only spare
parts supplied or approved by
Viessmann.
Safety instructions
Safety instructions
(cont.)
5816563
