24
Reducing the stagnation time
If there is an excess of solar energy, the speed of the
solar circuit pump is reduced before the maximum cyl-
inder temperature is reached (coding address "08").
This causes an increase in the differential between col-
lector temperature and cylinder temperature. The heat
transfer to the DHW cylinder is reduced, which delays
stagnation.
The temperature differential for reducing the stagna-
tion time is adjustable in coding address "0A".
This function can only be implemented in systems with
a variable speed solar circuit pump.
Target temperature control
System with one DHW cylinder
Set code/parameter "10:1" (target temperature control
switched on).
As well as
depending on the selected start tempera-
ture differential, the solar circuit pump is only started if
the collector temperature exceeds the value set in cod-
ing address "11".
System with 2 DHW cylinders
Set code/parameter "10:1" (target temperature control
switched on).
When the temperature of a DHW cylinder has excee-
ded the value set in coding address "11", solar heating
is transferred to the second DHW cylinder.
Monitoring the flow rate
If the solar circuit pump is running, the collector tem-
perature is > 100 °C for longer than 30 min and the dif-
ferential to the cylinder temperature is > 50 K, fault
message "9E" will be issued.
Monitoring of night circulation (not in conjunction with heat pumps)
Code 0D:1.
Unwanted flow rates in the solar circuit (e.g. at night)
are captured. For this, the night-time collector temper-
ature must exceed the outside temperature by 10 K.
The captured situations with unwanted flow are repor-
ted to the control unit of the heat source.
The situations can be called up under
"Diagnosis
solar"
(weather-compensated control unit) or
"Brief
scan"
(constant temperature control unit).
Heat statement (solar yield)
The following factors are taken into consideration
when calculating the heat amount:
■
Differential from collector and cylinder temperature
■
Flow rate
■
Type of heat transfer medium
■
Runtime of solar circuit pump
Note
The displayed values cannot be used for billing by the
power supply utility.
Interval function
Set code/parameter "07:1".
Activate the interval function in systems where the col-
lector temperature sensor is not in an ideal location, to
prevent a time delay in capturing the collector temper-
ature.
Function description – version with SM1
Version with SM1 and KM-BUS (solar DHW heating)
(cont.)
6131981
Appendix
