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EB 5573 EN
Functions of the heating circuit
Summer mode only becomes effective when the controller is in automatic mode ( ).
6.5 Buffer tanks systems Anl 16.x
A heating characteristic based on a gradient or four entered points can be set in PA1 for the
buffer tanks in systems Anl 16.x. A buffer tank set point for day operation and a buffer tank
set point for night operation can be set without outdoor sensors in the customer level. An ex-
ternal demand transmitted from secondary controlled heating circuits, DHW circuit or an ex-
ternal request (over device bus, 0 to 10 V or binary signal) can override the current buffer
tank set point. The maximum demand is indicated as the buffer tank set point for SF1. If the
temperature falls below the buffer tank set point at SF1, charging of the buffer tank is started.
The set point of the charging temperature is determined by the 'Minimum set point to charge
buffer tank' parameter setting in the PA1 level. The automatic adaptation ('OT' setting) caus-
es the set point of the charging temperature to always be above the current buffer tank set
point by the value entered in 'Charging temperature boost'. Every other value entered in
'Minimum set point to charge buffer tank' is used as the minimum set point for the charging
temperature which first starts to be variable at higher buffer tank set points. When a return
flow temperature sensor RüF1 is used, the charging pump SLP (CO1 > F22 - 1) is first re-
leased to avoid cold charging when the temperature measured at RüF1 has reached the
same temperature measured at SF1. The 'Stop charging of the buffer tank' parameter (PA1,
default = OT) determines under which conditions the charging of the buffer tank is stopped.
The automatic adaptation ('OT' setting) causes the buffer tank charging to be stopped when
the temperature in the buffer tank reaches the value ('Buffer tank set point' + 'Hysteresis of
buffer tank'. Every other value entered for 'Stop charging of the buffer tank' is rated as a
fixed switch-off temperature for the buffer tank charging. When SF2 (CO1 > F06 - 1) is con-
figured, SF2 is always used to stop the charging of the buffer tank. The storage tank
charging pump is not switched off until the lag time (entered 'Valve transit time Ty' for HC1
multiplied by 'Lag time of charging pump') has elapsed. The operation of the feeder pump
UP1 is either determined by the ZP time schedule or prompted over an external demand. For
systems with downstream control circuits, either only this external demand or the demand of
the downstream control circuits causes the feeder pump UP1 to be activated, depending on
the CO5 > F14 setting.
In systems Anl 16.3, 16.4 and 16.6, a solar circuit is integrated, which uses sensor SF2 for
control. The collector circuit pump CP is activated when the temperature at the collector sen-
sor RüF2 is higher than that at storage tank sensor SF2 by the value entered in 'Solar circuit
Note
Summary of Contents for TROVIS 5573
Page 144: ...144 EB 5573 EN Key number 1732...
