en
20
Installation
Commissioning
Adjustments
Tr
oubleshooting
Data comm
unication
Sliding set value
The
Sliding set value
function can be used for
adapting the hot water set temperature in the case of
insuffi cient store temperature. The function prevents
the primary pump from being run at 100 %, which
would unnecessarily mix the store contents and thus
destroy the store stratifi cation.
If the store fl ow temperature falls below the limit
value
T-HWset
+
∆
T sliding
, T-HW set will be
Adjustment channel
Description
Adjustment range / selection Factory setting
T-HW set sl.
Activation of the function
Yes, No
No
∆
T sliding
Temperature difference
2.0 … 20.0 K
5.0 K
back
Main menu / Hot water / Sliding set value
Heat exchanger mode
The
HX start
sub-menu can be used to adjust all
values for the operation of the heat exchanger.
3 heat exchanger modes are available. They enable
different temperature conditions of the heat ex-
changer at the beginning of a draw-off.
Adjustment channel
Description
Adjustment range / selection Factory setting
HX mode
Heat exchanger mode
Cold, Hot, Time
Cold
Cold start
Cold start pump runtime
10 … 600 s
120 s
∆
T cold start
Cold start temperature difference
-30 … +30 K
-5 K
Speed cold
Cold start pump speed
30 … 100 %
100 %
HX set value
Heat exchanger set temperature
10 … 60 °C
40 °C
HX set hyst
Heat exchanger hysteresis
1 … 10 K
2 K
Speed hot
Speed hot mode
15 … 100 %
25 %
Timer
Timer
-
-
Days of the week
Day selection
All days, Monday … Sunday,
Continue
-
Timer
Time frame adjustment
00:00 … 23:59
-
back
Main menu / Hot water / HX start
HX mode Cold
The primary pump is only activated when there is a
draw-off (cold start). At fi rst, the pump is run at the
adjusted
Speed cold
. As soon as the
Cold start
time has elapsed or the adjustable temperature dif-
ference
∆
T cold start
(reference sensors are S1
and S2) is exceeded, the cold start phase is com-
pleted. The controller switches to the pump speed
calculated.
HX mode Hot
The heat exchanger is permanently kept at the adjust-
ed
HX set
temperature (hot start). For that purpose,
the temperature at the store fl ow sensor is meas-
ured. If the temperature at this sensor falls below the
adjusted HX set value, the primary pump is run at the
adjusted
Speed hot
. When
HX set
+
HX set hyst
is exceeded, the primary pump is switched off.
HX mode Time
This mode is a combination of the other two modes.
With the timer, different days and time frames can
be adjusted. Within the time frames, the
HX mode
Hot
is active, outside the time frames, the
HX
mode Cold
is active.
decreased accordingly. The primary pump speed is
then controlled such that the new set value is per-
manently kept.
When the HX mode Cold is activated, the sliding set
value adaptation will start only if the cold start phase
has been completed.
T-HW set will only be decreased down to the lower
limit temperature of 20 °C.
Note:
In some systems it is recommended to
place the fl ow sensor S1 into the upper
store zone or not to activate the
sliding
set value mode
respectively.
