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Siemens Building Technologies
Basic Documentation RVP540 / RVP550
CE1P2488en
HVAC Products
General control processes
04.11.2009
6.2 Slave pointer for the buffer storage tank
The buffer storage tank collects the heat demand signals from the different heating
circuits and stores the maximum values.
Every night at midnight, the maximum demand is reduced by 5 % (referred to 0). The
slave pointer will be readjusted in the upward direction only when a higher heat de-
mand from one of the consumers is received.
A demand from the consumers for lower temperatures will be ignored.
The slave pointer does not affect the operation of the oil- or gas-fired boiler or the
automatic heat generation lock.
2392
Z
09
°C
t
*
20
40
80
60
100
*
*
*
*
*
*
*
*
*
*
24:00
24:00
24:00
24:00
24:00
24:00
24:00
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
* *
*
*
*
*
*
= different heat demand signals
The value of the slave pointer can be manually reset on operating line 456 (to do this,
press the + / - buttons simultaneously for 3 seconds).
The slave pointer will also be reset when switching the controller off.
6.3 Setpoint boost for the combi storage tank
(KoSp 1 – 3)
•
Prevents cold water from entering the combi storage tank
•
Ensures stratification in the storage tank
In the case of combi storage tanks with no diverting valve (KoSp1 – 3), the lower part of
the storage tank cannot be charged independently like with combi storage tanks using
a diverting valve.
If the lower part of the storage tank shall be recharged, it must be made certain that the
flow entering the upper part of the storage tank is not too cold (to maintain stratification
in the storage tank).
For that purpose – as soon as the lower part of the storage tank calls for heat (e.g. 40
°C) – the actual value acquired by the sensor at the top (e.g. 50 °C) will be compared
with the nominal d.h.w. temperature setpoint (operating line 26, e.g. 55 °C).
The lower of the 2 values will be passed to heat generation as the setpoint.
If, during charging, the heat source receives a greater heat demand (e.g. from one of
the heating circuits), that heat demand will of course be valid.
Description
Note
Resetting
Benefit
Description
