DE DIETRICH BSL 200...400 - BESL 200...400 - Manual (Page 9)

WARNING
Never cut the power to the solar control system, even
during extended absences. The control system protects
the installation against overheating in summer when it is
running.
WARNING
Do not modify the control system parameters unless fully
conversant with them.
During extended absences, we recommend lowering the set point
temperature in the solar DHW calorifier to 45°C. When the user is
present, the set point must be set to 60°C.
BSL 150...400 BESL 200...400 2. Safety instructions and recommendations
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