Viessmann VITOTRONIC 300 Installation And Service Instructions Manual page 68

Function Description
Heating Circuit Control Unit of the Vitotronic 300-K
Example using the settings in the factory set condition
Legend
A Start of operation with standard room temperature
B Set boiler water or supply temperature in accordance
with the selected heating curve
C Set boiler water or supply temperature in accordance
with coding address "FA":
122° F + 20% = 146° F
(50° C + 20% = 60° C)
D Duration of operation with raised set boiler water or
supply temperature in accordance with coding address
"FB": 60 min.
68
Time in h
Vitotronic 300, GW5B & MW1B Installation and Service
(continued)
Control sequence
Mixing valve circuit
The mixing valve motor will not be controlled within the
"neutral zone" (±1 K).
Supply temperature drops
(Set value −1 K)
The mixing valve motor receives the signal "Mixing valve
open". The signal duration lengthens with an increasing
control differential.
The duration of pauses reduces with an increasing control
differential.
Supply temperature rises
(Set value +1 K)
The mixing valve motor receives the signal "Mixing valve
closed". The signal duration lengthens with an increasing
control differential.
The duration of pauses reduces with an increasing control
differential.