Siemens RVL471 - Heating Curve; Purpose; Basic Setting

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Siemens Building Technologies Basic Documentation RVL471 CE1P2524E
HVAC Products 10 Function block "Space heating" 23.10.2002
The change of the room temperature setpoint ∆T
Rw
is calculated according to the fol-
lowing formula:
VF
∆T
Rw
[ K ] =
2
( T
Rw
– T
Rx
)
T
Rw
T
R
T
Rw
The change of the flow temperature setpoint ∆T
Vw
resulting from the change of the
room temperature setpoint is calculated as follows:
∆T
Vw
[K] = ∆T
Rw *
( 1 + s )
where:
s Heating curve slope
TRw Room temperature setpoint
∆TRw Change of room temperature setpoint
−∆TRw Decrease of room temperature setpoint
+∆TRw Increase of room temperature setpoint
TRx Actual value of the room temperature
∆T
R
Room temperature deviation (T
Rw
- T
Rx
)
∆TVw Change of flow temperature setpoint
VF Gain factor
10.6 Heating curve
10.6.1 Purpose
With the space heating systems (plant types 1–x, 2–x, and 3–x), flow temperature con-
trol is always weather-compensated. The assignment of the flow temperature setpoint
to the prevailing outside temperature is made via the heating curve.
10.6.2 Basic setting
The setting of the heating curve is made via the bar or 2 operating lines. The following
settings are required:
• Flow temperature setpoint at an outside temperature of −5 °C
• Flow temperature setpoint at an outside temperature of +15 °C
The basic setting during commissioning is made according to the planning documenta-
tion or in agreement with local practices.