Samson trovis 5600, Mounting And Operating Instructions

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8.3 Forced operation of the pumps
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 a longer period 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 flow temperature limitation
The temperature difference between the flow and return flow indicates how well the energy is
used: the greater the difference, the higher the efficiency. A return flow sensor is sufficient to
evaluate the temperature difference when the network flow temperatures are fixed to a certain
temperature. The return flow temperature can be limited either to a value depending on the out-
door temperature (variable) or to a fixed set point. When the temperature measured at return
flow sensor exceeds the current return flow temperature limit, the set point of the flow tempera-
ture (flow temperature of the heating system, charging temperature) is reduced. As a result, the
primary flow rate is reduced and the return flow temperature falls.
In systems 2.1.0 and 2.2.0, the 'Max. return flow temperature' parameter (DHW–PA4) is used
for limitation in the primary circuit during DHW heating if it is greater than the parameter valid
for the primary circuit. The 'Limiting factor' determines how strongly the controller responds to
limit violations (P algorithm).
If the PI action is to be implemented, configure HC1–CO5–16 = ON. This allows the integral-ac-
tion component in the return flow temperature limitation algorithm of all control circuits of the
controller to be activated.
NOTICE
To keep the determined return flow temperature limit, make sure that:
– the heating characteristic is not selected to be too steep
– the speed of the heating pumps is not selected to be too high
– the heating systems are hydronically balanced.
Note: Using weather-compensated control with gradient characteristic, the return flow temper-
ature is limited to a fixed value by equating the 'Return flow temperature foot' and 'Max. return
flow temperature' parameters.
EB 5610 EN
81
System-wide functions