Air conditioner runs but does not cool the room effectively; air from indoor unit is only slightly cool.

Safety first: Turn off power before cleaning filters or coils. Avoid bending aluminum fins.

• Step 1 – Clean air filters: Open the front panel, remove filters, wash with mild soap and water, dry completely, and reinstall. Clogged filters are the most common cause of poor cooling.
• Step 2 – Clean indoor coil: With filters removed, inspect the evaporator coil. If heavily dusty, use a soft brush or a coil cleaner approved for aluminum fins. Do not spray water into electrical parts.
• Step 3 – Check temperature difference: Run the unit on maximum cooling for 15 minutes. Measure air temperature at the intake and outlet. A difference of 8–12°C typically indicates normal operation. Much less may indicate low refrigerant or other issues.
• Step 4 – Room conditions: Close doors and windows, reduce heat sources (ovens, direct sun), and ensure the unit capacity matches the room size.
• Technician tasks: If cleaning does not restore performance, a technician should check refrigerant charge, look for leaks in Ariston evaporator and condenser coils, and verify compressor operation.