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Siemens Building Technologies
Basic Documentation RVP540 / RVP550
CE1P2488en
HVAC Products
Description of the heating engineer settings
18.10.2002
Functions
4.67 Minimum limitation of the boiler temperature
(TKmin)
•
Maintaining a predefined minimum boiler temperature
•
Prevention of corrosion due to condensation in the case of noncondensing boilers
Minimum limitation of the boiler temperature is a protective function for the boiler. In
addition, minimum limitation of the setting range can be defined with setting 250
EXP
.
Setting range
Unit
Factory setting
TKmin
EXP
...Tkmax °C 40
Tkmin
EXP
Minimum limitation of the boiler temperature setpoint (setting on operating line 250
EXP
)
TKmax
EXP
Maximum limitation of the boiler temperature setpoint (setting on line 251
EXP
)
0 10 20 30 40 50 60 70 80 90 100 120
TV
max
min
akt
°C
23
92
Z
26
251
Actual value Tk of the boiler temperature
270
Minimum limitation Tkmin of the boiler temperature setpoint
250
EXP
Lowest minimum limitation Tkmin
EXP
of the boiler temperature setpoint
251
EXP
Maximum limitation Tkmax
EXP
of the boiler temperature setpoint
The setting ensures that the boiler temperature will not fall below the adjusted minimum
level TKmin. This prevents noncondensing boilers from being operated in the con-
densing range, thus reducing the risk of corrosion due to condensation.
The boiler temperature does not fall below Tkmin, even if the consumers called for a
lower temperature.
If, on operating line 257
EXP
, setting 2 is selected, the boiler temperature can also tem-
porarily fall below Tkmin.
Benefit
Description
Setting
Effect
Limitation
Exception
20
10
0
-10
-20
40
30
60
50
80
70
TK
TK
TK
TK
SD
K
23
71
Z
26
TA
°C
°C
w
min
max
gem
0
Legend
TK Boiler
temperature
TKw
Boiler temperature setpoint
Tkmin
Minimum limitation of the boiler
temperature
TKmax
maximum limitation of the boiler
temperature
SDK Switching
differential
TAgem
Composite outside temperature
