Heating Curve - Viessmann VITOCROSSAL 300 CU3A 35 Operating Instructions Manual

Vitocrossal 300 CU3A 26 to 199 Operating
Terminology
(continued)
Room
set-point
temperature
Example:
For outside temperature 7°F (-14°C):
A Underfloor heating system, slope 0.2 to 0.8
B Low temperature heating system, slope 0.8 to 1.6
C Heating system with a boiler water temperature in
excess of 167°F (75°C), slope 1.6 to 2.0
Room
set-point
temperature
Legend
A Changing the slope:
The gradient of the heating curves changes.
B Changing the shift:
The heating curves are shifted in parallel in a vertical
direction.
C Changing the standard room temperature (set
value):
The heating curves are offset along the "Set room
temperature" axis.
Slope
Outdoor temperature
Outdoor temperature

Heating curve

Heating curves illustrate the relationship between the
outside temperature, room temperature (set value) and
boiler water or (heating circuit) supply temperature. The
lower the outside temperature, the higher the boiler
water temperature or heating circuit supply temperature.
In order to guarantee sufficient heat and minimum fuel
consumption at any outside temperature, the conditions
of your building and your heating system must be
taken into consideration. For this, you can adapt the
heating curve yourself.
Note: If your heating system includes heating circuits with
mixing valves, then the supply temperature for the
heating circuit without mixing valve is higher by
a selected differential than the supply temperature
for the heating circuits with mixing valve.
The illustrated heating curves apply with the following
settings:
H Heating curve shift = 0
H Standard room temperature (set value) = 68°F (20ºC)
Note: Setting the slope or shift of the heating curve too
high or too low will not result in damage to your
heating system.
Both settings affect the shift of the supply
temperature, which may then be too low or
unnecessarily high.
Tips on when and how to change the heating curve
slope and shift are displayed by pressing ?.
Additional Information
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