Viessmann Vitosol100 - Page 87

4.8Additional Vitosolic 200 functions
87
VITOSOL
External heat exchanger
The relay switches the consumer ON if the
set start−up temperature differential is
exceeded, and switches it OFF if the actual
temperature drops below shutdown
temperature differential.
Cooling function
Function for dissipating excess heat. The
solar circuit pump and a consumer
connected to R4 are switched ON if the
maximum cylinder temperature and the
start−up temperature differential have
been reached; they are switched OFF if
the actual temperature drops below
shutdown temperature differential.
Special functions of tube collectors
Activate in systems with unfavourably
positioned collector temperature sensor.
The solar circuit pump is activated every
30 minutes (with variable adjustment) for
30 seconds, to prevent a time delay when
recording the collector temperature.
From 22:00 to 06:00 h inactive.
Collector cooling function
The solar circuit pump is switched OFF
when the set maximum cylinder
temperature is reached.
The pump is switched ON if the collector
temperature rises to the set maximum
collector temperature, until the actual
temperature falls 5K below that value.
In this case, the cylinder temperature may
continue to rise, but no higher than 90 ºC
(cylinder safety shutdown).
Reverse cooling function
When the collector cooling function has
been activated, the cylinder temperature
may continue to rise, but no higher than
90ºC (cylinder safety shutdown).
In the evening, the pump continues to
run, until the DHW cylinder has cooled
down to the maximum cylinder
temperature via the collector and
interconnecting pipework.
Information regarding the collector cooling and reverse cooling function
Always use a correctly−sized diaphragm
expansion vessel, to ensure solar heating
system safety even if the collector
temperature rises after all limit
temperatures have been reached.
In case of stagnation or if the collector
temperature continues to rise, the solar
circuit pump will be disabled or switched
OFF (collector emergency shutdown), to
prevent connected components suffering
from thermal overload.
Frost protection
At a collector temperature below +4 ºC,
the solar circuit pump will be started to
prevent collector damage. The pump is
switched OFF when +5 ºC has been
reached.
Parallel relay
Relay R5 is switched ON when the solar
circuit pump is running.
5822135 GB