Comfort comes from steady control. Start with room size. A unit that matches the space will cool fast and hold temperature without strain. Shade windows in strong sun and close doors to help the room settle.
Pick a sensible setting and let the unit work. A very low number may not cool faster and can waste energy. Use a gentle fan when the room is quiet and a stronger fan when the room is busy. Keep filters clean. A quick check every few weeks keeps airflow smooth and reduces dust.
Plan for sleep. A small change in temperature during the night can keep comfort while using less power. If your model supports a timer, set it to switch off when the room is stable.
These habits let a FELSEN air condition feel natural in daily life while the use of energy stays low.