I purchased an earlier version of this model and loved it! It was super quiet and cooled my studio apt well.  However after several years it developed a buzzing sound.  I purchased this unit to replace the older version and boy was I disappointed.  It does not cool my apt well and has to be set in a very low temperature causing the constant wind tunnel noise.  It also rattles emits an awful ratting noise.  I regret throwing away my older unit.