sauter equitherm EQJW126F001, Mounting And Operating Instructions

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Operational faults
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BA_EQJW126F001_EN001
6.4 Return flow temperature limitation
The temperature difference between the flow and return flow indicates how well
the en- ergy is used: the greater the difference, the higher the efficiency. A return
flow sensor is sufficient to evaluate the temperature difference when the flow
temperatures are pre- set. 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 RüF exceeds the limit
value, the set point of the flow temperature (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.
The Limiting factor determines how strongly the controller responds when the limit
val- ues are exceeded in either direction (PI algorithm).
If just proportional component is to be implemented, set CO5 -> F16 - 1. This
allows the integral-action component in the return flow temperature limitation
algorithm of all control circuits of the controller to be deactivated. The set point
reading (flow tempera- ture of the heating, charging temperature) blinks to
indicate that a return flow limitation is active in the control circuit concerned.
Note: Using weather-compensated control with gradient characteristic, the
return flow temperature is limited to a fixed value by equating the Base point of
return flow tempera- ture and Max. return flow temperature (PA1) parameters.
Functions WE Configuration
Return flow sensors RüF1 1 CO1, 2, 4 -> F03 - 1
1.0 KP (limiting factor) / 0.1 to 10.0
Return flow temperature 0 CO5 -> F16
limitation with P algorithm*
* If CO5 -> F00 - 1 is indicated, access to the return flow, flow rate and heat capacity
settings are
locked.
Parameters WE Parameter level /
Range
of values
Gradient, return flow 1.2 PA1 / 0.2 to 3.2
Level, return flow 0.0 °C PA1 / –30.0 to 30.0 °C
Base point of return flow 65.0 °C PA1 / 5.0 to 90.0 °C
temperature
Max. return flow temperature 65.0 °C PA1 , 4 / 5.0 to 90.0 °C