Potterton eurocondense four 125 kw Installation, Operation And Maintanance Manual page 100

9 Settings
100
Early on, late off: Additional boilers are switched on as early as possible
(output range min) and switched back off again as late as possible (out­
put range min). I.e. as many boilers as possible in operation or long run­
ning times for additional boilers.
Release integral source seq (3530)
A value generated from temperature and time. The lag boiler is switched
on when the set limit is exceeded.
Reset integral source seq (3531)
The following boiler will be switched off in case of exceeding the setpoint
Restart lock (3532)
The restart lock prevents switching a switched off boiler being switched
back on again. It is only released again after the set time period has
elapsed. This prevents the boiler switching on and off too often and ach­
ieves a stable operating condition of the system.
Switch on delay (3533)
Too frequent forward and back switching (cycles) of the boiler are avoided
by the switch-on delay and therefore a stable operating state is ensured.
Auto source seq ch'over (3540)
The sequence of lead boiler and following boiler is defined by the source
sequence changeover and in this way, the utilisation of the boilers in a
cascade is influenced. After the set time has elapsed, the boiler sequence
is changed. The boiler with next higher device address operates as lead
boiler.
The operating hours transferred from the generator to the cascade master
are decisive for calculating the hours run.
Auto source seq exclusion (3541)
None: The boiler sequence changes after expiry of the time set in prog.
no. 3540.
First: The first boiler in the addressing works as the lead boiler; for all
the other boilers the boiler sequence is changed after expiry of the time
set in prog. no. 3540.
Last: The last boiler in the addressing always remains the last boiler; for
all other boilers the boiler sequence is changed after expiry of the time
set in prog. no. 3540.
Leading source (3544)
The setting of the leading generator is only used in combination with the
fixed sequence of the generator sequence (prog. no. 3540). The generator
defined as the leading generator is always put into operation first, and
switched off last. The other generators are switched on and off in the se­
quence of the device address.
Return setpoint min (3560)
If the return temperature drops below the return setpoint set here, the re­
turn maintenance becomes active. The return maintenance enables influ­
ences on the consumers or use of a return controller.
Temp differential min (3590)
This function prevents too high cascade return temperatures and improves
the switch off behaviour of the cascade. If the temperature difference be­
tween the flow and return sensor is smaller than the minimal temperature
spread set here, a generator is switched off as early as possible independ­
ently of the set lead strategy. Once the temperature difference is sufficient
again, the set lead strategy is switched over again.
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