Viessmann Vitoladens 300-W Service Instructions For Contractors page 79

Control unit
(cont.)
DHW heating
The burner, the circulation pump and the
three-way valve are started or changed
over, if the cylinder temperature lies 2.5
K below the set cylinder temperature.
The set boiler water temperature is
adjusted 20 K higher than the set DHW
temperature (adjustable via coding
address "60"). The burner will be
switched OFF and the circulation pump
run-on time will begin, if the actual cylin-
der temperature exceeds the set cylinder
temperature by 2.5 K.
Internal extension H3
Boosting DHW heating
The booster heating function is activated
if a switching period is selected for the
fourth time phase.
The set temperature value for the heat-
ing boost is adjustable in coding address
"58".
Function description
79