Viessmann FB2B Installation And Service Instructions Manual page 115

Repairs
(cont.)
Draining the boiler on the heating water side
A
1. Close the shut-off valves on the heat-
ing water side.
2. Route hose at drain valve A into a
suitable container or drain outlet.
3. Open drain valve A and drain the
boiler as much as required.
Troubleshooting
115