Adjusting Heating Curves - Viessmann VITOTRONIC 300 Installation And Service Instructions Manual

Commissioning

Adjusting Heating Curves

Room
set-point
temperature
Example of outside temperature 7° F (−14° C)
Legend
A Underfloor heating system, slope 0.2 to 0.8
B Low temperature heating system, slope 0.8 to 1.6
C Heating systems with a boiler water temperature in
excess of 167° F (75° C), slope greater than 1.6
230 °F
(110 °C)
Legend
A Boiler water temperature or supply temperature
B Outside temperature
C Set room temperature
D Heating circuit pump OFF
E Heating circuit pump ON
48
Outdoor temperature
79 °F
(26 °C)
68 °F
(20 °C)
-4 °F
(-20 °C)
Vitotronic 300, GW5B & MW1B Installation and Service
The heating curves illustrate the relationship between
the outside temperature and the boiler water or supply
temperature.
To put it simply: The lower the outside temperature,
the higher the boiler water or supply temperature.
The room temperature, again, depends on the boiler
water or the supply temperature.
Settings in the factory set condition:
H Slope = 1.4
H Shift = 0
Selecting the set room temperature
Individually adjustable for each heating circuit.
The heating curve is offset along the axis of the set room
temperature. When the heating circuit pump logic function
has been enabled, it modifies the starting and stopping
characteristics of the heating circuit pump.
Standard set room temperature
Changing the standard room temperature from 68 to 79° F
(20 to 26° C)
Operating instructions