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3064816_201804
24. Parameter description
Cylinder heating commences as soon as the cylinder temperature sensor de-
mands heat. The heating circuit pumps would be constantly off if the appliance
were undersized, the cylinder were scaled up or if DHW were constantly drawn
off during DHW priority mode. The accommodation would then cool down
significantly. To limit this effect, it is possible to specify a maximum cylinder
heating time.
If the maximum set cylinder heating time has expired, fault message 52 appears
on the programming or display module.
The control unit reverts to heating mode and cycles in the selected rhythm
(HG20) between heating and cylinder heating mode, regardless of whether
the cylinder has reached its set temperature or not.
The "Max. cyl. heat time" function remains active even if parallel pump operation
is enabled. If HG20 is set to OFF, the "Max. cyl. heat time" function is disabled.
Set this parameter to OFF in heating systems with high DHW consumption,
e.g. hotels, sports facilities, etc.
Parameter HG20
Max. cylinder heating time
Factory setting: See table
Setting range: OFF/30 to 180 min
Individual setting:
_____
The control unit is equipped with an electronic boiler thermostat which has an
adjustable maximum shutdown temperature (maximum boiler water temper-
ature). The burner is switched off if this temperature is exceeded. The burner
will restart when the boiler water temperature has fallen by as much as the
burner switching differential.
Parameter HG22
Maximum boiler water temperature
TK-max
Factory setting: See table
Setting range: 50 to 90 °C
Individual setting:
_____
The excess temperature differential between the cylinder temperature and the
boiler water temperature during cylinder heating is selected with parameter
HG25.
The boiler water temperature continues to be limited by the maximum boiler
water temperature (parameter HG22). This ensures that, even in spring and
autumn, the boiler water temperature is higher than the cylinder temperature,
thereby ensuring short heating times.
Parameter HG25
Excess boiler temperature
for cylinder heating
Factory setting: See table
Setting range: 1 to 30 °C
Individual setting:
_____
The control unit is equipped with an electronic boiler thermostat which has an
adjustable minimum start temperature. The burner is switched on subject to
the cycle block if this temperature is not achieved when heat is demanded. If
there is no heat demand, the minimum boiler water temperature TK-min may
also be undershot.
Parameter HG21
Minimum boiler water temperature
TK-min
Factory setting: See table
Setting range: 20 to 90 °C
Individual setting:_____
The DHW temperature is factory-set to 65 °C. If, for commercial reasons, a
higher DHW temperature is required, a maximum of up to 90 °C can be enabled.
If pasteurisation has been enabled, the DHW cylinder will be heated to 65 °C
during the first cylinder heating of the day, subject to parameter HG23 being
set to this temperature or higher.
Please note:
Take adequate measures to prevent scalding.
Parameter HG23
Maximum DHW temperature
Factory setting: See table
Setting range: 50 to 90 °C
Individual setting:_____
