Siemens RVA53.242 - 5.7 Pump overrun time

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Siemens Building Technologies Basic Documentation RVA63.242, RVA53.242 CE1P2373E
Landis & Staefa Division Description of OEM settings 26.03.2001
5.7 Pump overrun time
Protects the boiler against overtemperatures.
Overrun of the pumps makes certain that residual heat will be carried away, thus
preventing the manual safety limit thermostat from responding.
Setting range Unit Factory setting
0...20 min 5
All pumps that - at the time of burner shut-down - were operating, continue to run for
the period of time set here. The behavior is the same as with burner shut-down when,
with the burner deactivated, the boiler temperature demand becomes invalid. Also, the
previous flow temperature setpoint is maintained to make certain the mixing valve will
be open during the same period of time.
ON
OFF
t
BR
Q
t
TVNw
TVRw
2373Z28
Y
t
tPN
t
HK
ON
OFF
HK Operating mode
Q Pumps
Y Mixing valve
TVNw Nominal flow temperature setpoint
TVRw Reduced flow temperature setpoint
tPN Pump overrun time
Nominal operation
Reduced operation
Benefit
Description
Setting
Effect
Example