Operating Instructions

Table Of Contents
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Siemens RXB (KNX) application library RXB Description of functions for FC-10, FC-11, FC-12, FC-13 CM110385en_08
Building Technologies Control sequences 2013-06-17
8.4 Fan-coils with LTHW radiator (FNC18)
LTHW radiator applications have a proportional control sequence. The controllers
operate with a PI algorithm optimized for thermal or motorized valve actuators. (For
simplicity, the diagram below shows only the P-control action.)
The radiator sequence can also be used for other heating types, e.g. floor heating.
However, the control parameters are not optimized for this.
The heater battery of the fan-coil operates in a cascade with the radiator.
The control sequences come into operation at the effective heating setpoint.
B1
YHC
Q1
YH
T
D3
B1
T
T
10385S08
100
0
TRC]
Y [%]
SpH SpC
Change-over
YH
H
C
100
0
TRC]
Y [%]
SpH SpC
Change-over
YHC
H
C
10385D16
YHC
Y Output signal
TR Room temperature
SpH Effective heating setpoint
H Heating sequence
YH Heating valve (radiator)
YHC Heating/cooling valve (fan coil)
B1 Return air sensor
Q1 Fan
8.4.1 Configuration and parameter setting
The radiator as an additional heating sequence has its own settings for the valve
actuator and runtime. The principles are described in section 8.1.4.