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Expert area
Part 3: General function description
42
Hot water generation
The programmed hot water temperature is stabilised by
switching the hot-water cylinder charging pump and the
burner. Storage tank charging starts when the storage tank
temperature drops below the temperature setting by 5K.
Storage tank charging stops when the temperature setting
is reached.
Frost protection function
The frost protection circuit prevents the heating system
from freezing by automatically switching heating operation
on.
Outdoor sensor frost protection
If the measured outside temperature drops below the set
frost protection temperature the room temperature setting
is set to 5°C for the relevant heating circuit. The heating
circuit is enabled:
•
the pumps are switched on
•
the heat request is sent to the HS
"----" => outdoor sensor frost protection deactivated
The function stops when the outside temperature
increases to 1K above the frost protection temperature
setting.
HS frost protection / header frost protection
Header frost protection is activated when the header
temperature drops below 5°C. The cascade is switched on
until the header temperature exceeds "MIN T-COLL“.
Flow or storage tank sensor frost protection
The sensor frost protection is activated when the flow or
storage tank temperature drops below 7°C. Only the
relevant pump is switched on.
The sensor frost protection is deactivated when the flow or
storage tank temperature increases to above 9°C.
Frost protection via room sensor
If the room temperature drops below 5°C the frost
protection function is activated.
The room temperature setting for the relevant heating
circuit is set to 5°C. The heating circuit is enabled:
•
the pumps are switched on
•
the heat request is sent to the boiler
EEPROM check
Every 10 minutes, a check is conducted automatically in
order to establish whether the settings of the controller lie
within the specified limits. If a value is found to be out-of-
range, it is substituted by the related default value. The
range transgression is indicated by the blinking
E
and the
error number 81.