Overview
- Grundeigentümer‑Versicherung warns the radiator snowflake setting only holds roughly 6°C at the heater and does not protect externally routed pipes.
- GEV advises leaving radiators at least on level 1 and keeping all rooms at or above 14°C during absences to reduce freezing risk.
- Umweltbundesamt targets remain 20°C in living rooms, 18°C in kitchens, and 17°C in bedrooms, with about a 2°C reduction acceptable when you leave home.
- Short, full-window ventilation three times daily for five to ten minutes—cut to three to five minutes below 0°C—helps prevent condensation, while tilted windows waste heat and air poorly.
- Energy advisers say steady low heat is more efficient than reheating cold rooms; use lower thermostat settings for longer (level 3 is about 20°C), keep radiators unobstructed, and aim for 40–60% indoor humidity.