Caution
Limiting the boiler rise may only be performed if a modulating heat
circuit pump is configured, i.e. if program no. 6085 (Function
output P1) is assigned to a heating circuit pump.
Temp differential nominal (2317)
The spread between boiler flow temperature and boiler return temperature
is called the temperature rise.
For operation with a modulating pump, the temperature rise is specified
with this parameter.
Pump modulation (2320)
None: The function is switched off.
Demand: Actuation of the boiler pump occurs at the speed calculated for
the DHW pump during DHW mode or with the highest calculated speed
for the max. 3 heating circuit pumps during pure heating mode.
The calculated pump speed for heating circuit 2 and 3 is only evaluated
if these heating circuits are also dependent on the setting of the
diverting valve (parameter
boiler pump/DHW diverting valve control
).
Boiler setpoint: The boiler pump modulates its speed so that the current
setpoint (DHW or buffer storage tank) is achieved on boiler flow. The
speed of the boiler pump should be increased within the specified limits
until the burner has reached its upper output limit.
Temp differential nominal: The boiler output is controlled to the boiler
setpoint.
The control of the pump speed controls the speed of the boiler pump so
that the nominal rise between the boiler return and boiler flow is
observed.
If the actual rise is larger than the nominal rise, the pump speed is
increased, otherwise the pump speed is reduced.
Burner output: If the burner is operated with low output then the boiler
pump should also run at low speed. During high boiler output the boiler
pump should run at high speed.
Pump speed min (2322)
The working range can be defined in percent of output for the modulating
pump. The control translates the percent data internally to speeds.
The value 0% corresponds to the minimum pump speed.
Pump speed max (2323)
The pump speed and with it, the power consumption can be limited via the
maximum value.
Output nominal (2330) and Output basic stage (2331)
The settings under prog.no. 2330 and prog.no. 2331 are necessary when
setting up boiler cascades with boilers of different output.
Output at pump speed min (2334) and Output at pump speed
max (2335)
If the option burner output is selected under prog. no. 2320, the boiler
pump is operated up to the set burner output under prog. no line 2334 to
minimum pump speed. From the burner output set under prog. no. 2335
the boiler pump is operated on maximum pump speed. If the burner output
lies between these two values, the pump speed for the boiler pump is
given by linear conversion.
Fan parameters
Prog.no. 2441: With this parameter the maximum boiler capacity can be
limited in heating mode.
Prog.no. 2444: With this parameter the maximum boiler capacity for the
DHW mode can be restricted.
Important
These are calculated values. The actual output must be calculated
using a gas meter, for example.
9 Settings
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