Viessmann Vitovalor PT2 Installation And Service Instructions For Contractors page 138

Troubleshooting
Repairs
(cont.)
Draining gas condensing module on the heating water side
D
B
A
C
Fig. 85
HK
Fig. 86
Draining the fuel cell module system separation circuit
Fig. 87
138
C
A
B
D
E
G F
C
A
B
1. Shut off connections
A
water side.
2. Fit the supplied short hose to the drain valve
or and feed into a drain connection.
D
3. Open drain valve or
C
Note
If necessary, open the air vent valves on the two
outer shut-off valves above the modules.
4. If necessary, continue to drain at drain valves
F , G , H and K . The drain hose is attached to
the fuel cell module.
1. Put the fuel cell module into maintenance mode:
See page 72.
2. Switch the ON/OFF switch of the fuel cell module
to OFF: See page 65.
3. Attach the drain house to valve
to a drain.
4. Open the drain valve on the underside of fitting
by turning screw to undo it and pulling it down-
B
wards.
Note
Check whether the automatic air vent valves
are open at the connection lines.
and on the heating
B
C
.
D
,
E
and connect it
A
A
C