Reverse Cooling Function; Frost Protection Function - Viessmann VITOSOLIC 200 Installation And Service Instructions Manual

Reverse cooling function

■ Activating this function is only appro-
priate if the collector cooling function
has been enabled.
■ The collector cooling function leaves
the solar circuit pump switched ON
when the set temperature "Tcyl set"
has been reached, so as to prevent the
collector from overheating.
■ In the evening, the solar circuit pump
will run on for as long as required to
cool the consumer via the collector
and the pipework down to the selected
set temperature "Tcyl set".
Note
Ensure the intrinsic safety of the solar
thermal system by accurately sizing the
diaphragm expansion vessel, even if the
collector temperature continues to rise
after the system has reached all limit
temperatures.
The solar circuit pump will be locked out
or stopped in case of stagnation or when
the stop temperature "Tcolemoff" (see
page 118) is reached. This prevents a
thermal overload of the connected com-
ponents.

Frost protection function

■ To prevent collector damage.
■ Activate only when using water as heat
transfer medium.
■ Solar circuit pump on:
Collector temperature "Tcol" ≤ +4 ºC.
■ Solar circuit pump off:
Collector temperature "Tcol" ≥ +5 ºC.
Function description
Make the following settings at the
solar control unit:
Main menu
■ "Solar"
■ "Options"
– "Ret.cool.fct"
Set "Yes".
Make the following settings at the
solar control unit:
Main menu
■ "Solar"
■ "Options"
– "Frost prot."
Set "Yes".
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