Viessmann VITOCAL 242-G Installation And Service Instructions Manual page 190

Buffer cylinder control settings
Excess reaction
(cont.)
2 Heat will be drawn off, even if the excess heat being created is not critical
for the heat pump.
Access
"Device settings"
"Programming"
"Further menu items"
190
"Buffer cylinder"
"Excess reaction"
(l/m)
Standard setting
Setting range
2
0 to 2