Samson TROVIS 5500 - Forced Pump Operation; Return Flow Temperature Limitation

100 EB 5573-1 EN
System-wide functions
NOTICE
Frost protection operation of a pump, a heating circuit or the DHW circuit is only ac-
tive when the
frost protection icon is displayed. In the stand-by mode ( ) xed set
point control without outdoor temperature sensor does not include frost protection.
8.3 Forced pump operation
When the heating circuit pumps have not been activated for 24 hours, forced operation of
the pumps is started between 12.02h and 12.03h. This is done to avoid that the pumps get
stuck when they are not operated for long periods of time. In the DHW circuit, the circulation
pump is operated between 12.04h and 12.05h, the other pumps between 12.05h and
12.06h.
8.4 Return ow temperature limitation
The temperature difference between the ow and return ow in a network indicates how well
the energy is used: the greater the difference, the higher the efciency. A return ow sensor
is sufcient to evaluate the temperature difference when the ow temperatures are pre-
dened. The return ow temperature can be limited either to a value depending on the out-
door temperature (variable) or to a xed set point. When the return ow temperature mea-
sured at return ow sensor exceeds the limit, the ow temperature set point is reduced. When
the temperature measured at return ow sensor RüF exceeds the return ow temperature lim-
it, the set point of the ow temperature (ow temperature of the heating system, charging
temperature) is reduced. This causes the primary ow rate to be reduced and the return ow
temperature to drop. In systems Anl2.x and 4.1, the 'Max. return ow temperature' parame-
ter (PA4 level) is used for limitation in the primary circuit during DHW heating if it is greater
than the parameter valid for the primary circuit. The 'KP' (limiting factor) determines how
strongly the controller responds when the limits are exceeded in either direction (PI algo-
rithm).
If just the proportional component is to be implemented, set CO5>F16 - 1. This allows the
integral-action component in the return ow temperature limitation algorithm of all control
circuits of the controller to be deactivated. The set point reading (ow temperature of the
heating, charging temperature) blinks to indicate that a return ow limitation is active in the
control circuit concerned.