The condensing coils will always be on the "warm" side of the air conditioner. That is, on the side that faces outside of the room to be cooled. Air is drawn into the back of the air conditioner on the sides through vent slots and is blown directly out through the condenser coils. If the coils get clogged with lint, dust and dirt the cooling system cannot provide the cooling necessary. To clean the coils it will be necessary to remove the entire cover of the air conditioner or pull it out of the wall to gain access to the coils. They can be cleaned by blowing compressed air at them or by using a soft bristle brush to wipe the dirt off. It is important to also clean any dirt or lint build-up in the bottom of the air conditioner so the condensate water will be picked up by the condensing fan slinger properly.