Viessmann VITOCAL 242-G Installation And Service Instructions Manual page 120

Commissioning, inspection, maintenance
Further details regarding the individual steps
6. Use a chemical cleaning agent to
remove hard deposits that cannot
be removed with a high pressure
cleaner.
!
Please note
Cleaning agents contain-
ing hydrochloric acid can
attack the material of the
DHW cylinder.
Never use such cleaning
agents.
7. Thoroughly flush the DHW cylin-
der after cleaning.
8. Close drain valve B.
9. Insert new gasket G underneath
flange lid F.
Note
If the impressed current anode is
to be replaced (see page 121),
carry out the required steps now.
120
(cont.)
10. Fit flange lid F with impressed
current anode H and earth strap
K of the impressed current
anode. Tighten the screws with a
maximum torque of 25 Nm.
!
Please note
Contact between the
impressed current anode
and the internal indirect
coil leads to a failure of the
anode. This leads to corro-
sion damage on the DHW
cylinder.
Test the resistance of the
impressed current anode
in accordance with the fol-
lowing description.
11. Measure the resistance between
connectors E and K. The resis-
tance must veer towards infinity. If
the resistance is significantly
lower, carry out a detailed instal-
lation check (the anode may con-
tact the indirect coil).
12. Slide anode connector D onto
push-on tab E.
Note
Never interchange cables/leads.
13. Install thermal insulation hood
C.
14. Open shut-off valve A (only for
the Vitocal 242 internal).
15. Check the fittings on the heating
and DHW side for leaks and
tighten, if required.