46
Solar control
The solar control starts or stops a
solar pump
based on the differential between the
collector
tem
-
perature and a
reference
temperature (e.g. temperature at the bottom of a cylinder). Option: use of
a limit sensor (e.g. temperature at the top of the cylinder).
Start conditions for the solar pump:
1. The
collector temperature
must exceed the minimum collector temperature and must not
exceed the maximum threshold "T.coll. max.".
2. The set
differential
between the collector temperature and the reference temperature must be
exceeded.
3. The
reference temperature
must not yet have reached its maximum limit "T.ref. max.".
If the
optional
limit sensor is used, it must not have reached the
limit temperature
.
Example
(without limit sensor) with a link to the settings:
When the collector exceeds a certain temperature (e.g. 130 °C) the system comes to a standstill and
it is assumed that steam is present in the collector, usually making circulation of the heat transfer
medium impossible. For this reason, the collector sensor has an adjustable maximum limit,
T.coll.
max
. If that limit is exceeded, the solar function stops and is not enabled again until the collector tem
-
perature drops below a certain level (usually 110 °C). This protective function prevents overheating
of the solar pump due to lack of circulation.
The maximum cylinder temperature
T.cylinder, max bottom
should be selected according to wheth
-
er the cylinder is used as a DHW or as a buffer cylinder.
