We were not getting the building to cool down although the air appeared to be working. We called for service to Sheldons AC and had a tech to our office within an hour. We were anticipating a major replacement of the unit, but after cleaning and adjusting the fluid levels our office began to cool again! Sheldons saved us some big bucks and explained how to do some preventative maintenance to keep our unit working properly in the future. Now what AC company will give you tips on how not to have to call them in the future??? That was service!