Draining The Boiler On The Dhw Side - Viessmann Vitodens 222-F Installation And Service Instructions For Contractors

Checking the anode earth current with an anode...
3. Connect the tester (up to 5 mA) in series across
tab B and earth cable
■ If the current measures
magnesium anode is OK.
If the current measures < 0.3 mA or if there is no
■
current at all, inspect the protective magnesium
anode visually (see page 46).

Draining the boiler on the DHW side

Fig. 37
A .
0.3 mA the protective
>
Commissioning, inspection, maintenance
(cont.)
1. Connect the hose to the drain valve and route it
into a suitable container or drain outlet.
Note
Ensure adequate ventilation in the DHW pipework.
2. Turn drain valve from lever position
tional) to lever position
Lever position : the DHW circuit in the appli-
■ B
ance excluding the DHW cylinder is drained via
the cold water connection.
■ Lever position : the DHW circuit in the appli-
C
ance and DHW cylinder are drained via the hot
water connection. The cold water connection
remains filled.
(opera-
A
or as required.
B C
45