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Siemens Building Technologies
Basic Dokumentation RVA63.280, RVA53.280
CE1P2374E
Landis & Staefa Division
19.04.2001
Heating circuit
3.11
Boost of flow temperature setpoint mixing
valve (UEM)
Efficient control of mixing heating circuits.
By adding cooler return water to the water delivered by the boiler, boiler temperature
variations will be smoothed out, enabling the mixing valve to produce more constant
flow temperatures.
However, to achieve the desired mixing, the actual value of the boiler’s flow
temperature must be higher than the required mixing valve flow temperature setpoint. If
this is not observed, the setpoint cannot be attained within the required period of time.
Hence, this setting raises the mixing valve flow temperature setpoint.
Setting range
Unit
Factory setting
0...50
°C (K)
10
The setting raises the boiler temperature setpoint when the mixing heating circuit calls
for heat.
Increase:
Reduced risk of flow temperature undershoots
Decrease:
Flow temperature undershoots possible
The controller generates the boiler temperature setpoint based on the boost set here
and the current flow temperature setpoint:
The greater the temperature differential between boiler flow and mixing heating circuit,
the quicker the required setpoint can be reached.
TVw
Flow temperature setpoint
Setting on line 30
OEM
Boost
Total
Boiler temperature setpoint
Also refer to "heating curve slope" in Index.
Benefit
Description
Setting
Effect
Boiler boost
Note
