While cooling, the air conditioner can generate a difference in temperature of more than 10°C. If the temperature difference between the air entering the air conditioner and exiting it is less than 10°C, then you should check for the following:
- Air ventilation: The air ventilation should be closed to prevent outside air from entering the unit, thus reducing its efficiency.
- Condensing coils: The condensing coils should be clean and not clogged with lint, dust and dirt. This will prevent the system from cooling efficiently. Remove the entire cover of the air conditioner or pull it out of the wall to access the coils. Clean the coils by blowing compressed air on them or using a soft bristle brush to wipe the dirt off.
Additionally, clean any dirt or lint build-up in the bottom of the air conditioner so the condensing fan slinger will pick up water for condensation easily.