Viessmann VITODENS 111-W Installation And Service Instructions Manual page 50

Troubleshooting
Repairs
(cont.)
Checking and cleaning the plate heat exchanger
Note
Drain the boiler on its heating water and
DHW side.
A
2x
B
1. Undo plate heat exchanger A
(screws B) and pull away from the
front.
2. Check the connections on the heat-
ing water and DHW side for contam-
ination and scaling; if required,
replace the plate heat exchanger.
50
3. Install in reverse order with new gas-
kets.