Heating Circuit Control Unit Of The Vitotronic 300 - Viessmann VITOTRONIC 300 Installation And Service Instructions Manual

Vitotronic 300, GW5B & MW1B Installation and Service
Heating Circuit Control Unit of the Vitotronic 300-K
Brief description
H The control unit has control circuits for one system
circuit A1 (heating circuit 1) and two heating circuits
with mixing valve M2 (heating circuit 2) and M3
(heating circuit 3).
H The set supply temperature of every heating circuit is
determined from the following parameters:
– Outside temperature
– Set room temperature
– Operating mode
– Heating curve slope and shift
H The supply temperature of the system circuit
corresponds to the common system supply temperature.
H The supply temperature of the heating circuits with
mixing valve is regulated by the gradual opening or
closing of the mixing valves. The mixing valve motor
control changes the actuating and pause times subject
to the control differential (control deviation).
Functions
The system circuit is subject to the boiler water
temperature and its control range limits.
The heating circuit pump is the only actuator.
The supply temperature of the heating circuits with
mixing valve is recorded by the supply temperature sensor
of the relevant heating circuit.
H Upper control limit: Electronic maximum supply
temperature limit Coding address "C6" in the "Heating
circuit..." group.
H Lower control range limit: Electronic minimum supply
temperature limit Coding address "C5" in the "Heating
circuit..." group.
Time program
In accordance with the time program in the "Heating
and DHW" heating program, the control unit regulates
between "Central heating at standard room temperature"
and "Central heating at reduced room temperature".
Every operating mode has its own set level.
4 time phases per day can be selected.
Outside temperature
A heating curve must be set for matching the control unit
to the building and the heating system.
The heating curve characteristics determine the set boiler
water temperature subject to outside temperature. An
average outside temperature is used for control purposes.
This comprises the actual and the adjusted outside
temperature.
Room temperature
In conjunction with the remote control and room
temperature hook-up (coding address "B0" in the
"Heating circuit..." group):
Compared with the outside temperature, the room
temperature has a greater influence on the set boiler
water temperature (changed via coding address "B2" in
the "Heating circuit..." group).
In conjunction with heating circuits with mixing valve:
For control differentials (actual value deviation) above
2 K room temperature, the influence can be increased
again (coding address "B6" in the "Heating circuit..."
group):
H Quick heat-up
The set room temperature must be raised by at least
2 K by the following measures:
– Enabling party mode
– Changing from central heating with reduced
temperature to central heating with standard
temperature
– Start optimization (coding address "B7" in the
"Heating circuit..." group)
Quick heat-up will stop when the set room temperature
has been reached.
H Quick setback
The set room temperature must be reduced by at least
2 K by the following measures:
– Enabling economy mode
– Changing from central heating with standard
temperature to central heating with reduced
temperature
– Stop optimization (coding address "C1" in the
"Heating circuit..." group)
Quick setback will stop when the set room temperature
has been reached.
Function Description
65