Boost Of The D.h.w. Charging Temperature; Maximum D.h.w. Charging Time; Setpoint Of Legionella Function - Siemens RVL471 Basic Documentation

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19.4 Boost of the d.h.w. charging temperature

The boost of the d.h.w. charging temperature in °C can be set on operating line 127.
The boost refers to the setpoint of the d.h.w. temperature.
The lower the setting of this value, the longer d.h.w. charging takes.
T [°C] = T + T
Lw BWw BW∆
Example:
Setpoint of d.h.w. temperature (T
Boost of the d.h.w. charging temperature (T
line 127)
Resulting setpoint of the charging temperature T
If thermostats are used, the boost of the d.h.w. charging temperature must still be set.

19.5 Maximum d.h.w. charging time

The maximum charging time for d.h.w. storage tanks can be set on operating line 129.
This function is always active, independent of the kind of d.h.w. priority (absolute, shift-
ing, or parallel).
As soon as d.h.w. charging starts, a counter records the charging time. If charging is
terminated before the set maximum charging time has expired, the counter will be set
to zero. A new charging cycle can commence at any time.
However, if charging takes longer than the set maximum time, charging will be stopped
and than locked for the same period of time. Then, charging will be resumed either until
the setpoint is reached or maximum limitation terminates the charging time again.
This function can be deactivated, in which case the charging time will not be limited.
T
BW
T
BWw
T - SD
BWw BW
B
WL
ON
OFF
D.h.w. charging locked
B D.h.w. charging
WL
ON D.h.w. charging ON
OFF D.h.w charging OFF
t Time
t Maximum charging time
Lmax
T D.h.w. temperature
BW
TBWw D.h.w temperature setpoint
SDBW Switching differential d.h.w.

19.6 Setpoint of legionella function

On operating line 130, the setpoint of the legionella function can be adjusted or the
function deactivated. This function raises the d.h.w. temperature periodically, thus
making certain that legionella viruses will be killed. For description, refer to chapter
"23 Function block "Legionella function"
Basic Documentation RVL471
19 Function block "D.h.w. storage tank"
, operating line 26)
BWw
, operating
BW∆
Lw
t t
Lmax
Lmax
= 50 °C
= 10 °C
= 60 °C
t
t
CE1P2524E
23.10.2002