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Siemens Switzerland Ltd  User manual RVS61.843 CE1U2355en_02 
HVAC Products  6 The settings in detail  23. November 2007 
Room influence 
Line no.  Operating line 
HC1 HC2 HC3P    
750 1050 1350   Room influence 
 
Compensation variants 
When a room temperature sensor is used, there is a choice of 3 different types of 
compensation.  
 
Setting  Type of compensation 
− − − % 
Pure weather compensation * 
1…99 %  Weather compensation with room 
influence 
100 % 
Pure room compensation  
* Outside sensor required. 
 
The flow temperature is calculated via the heating curve, depending on the composite 
outside temperature. 
This type of compensation calls for correct adjustment of the heating curve since in that 
case the control gives no consideration to the room temperature
. 
 
The deviation of the actual room temperature from the setpoint is measured and taken 
into account when controlling the temperature. Heat gains can thus be considered, 
ensuring more accurate room temperature control. The effect of the deviation is set as 
a percentage figure. The better the reference room (correct room temperature, correct 
mounting location, etc.) the higher the value can be set. 
• Example: 
Approx. 60%  Good reference room conditions 
Approx. 20% 
Unfavorable reference room  
 
To activate the function, following must be considered: 
•  A room temperature sensor must be connected 
•  The ”Room influence“ setting must be between 1 and 99 
•  There should be no thermostatic radiator valves in the reference room (mounting 
location of room sensor) (If such valves are present, they must be set to their fully 
open position)  
 
The flow temperature is controlled depending on the room temperature setpoint, the 
current room temperature and the progression of the room temperature. For example, a 
slight room temperature increase leads to an immediate drop of the flow temperature. 
 
To activate the function, following must be considered: 
•  A room temperature sensor must be connected 
•  “Room influence“ must be set to 100% 
•  There should be no thermostatic radiator valves in the reference room (mounting 
location of the room sensor). (If such valves are present, they must be set to their 
fully open position) 
 
Pure weather 
compensation 
Weather compensation 
with room influence  
 
Pure room  
compensation