Customers drains where drains for upstairs sink tie into main under ground has a faulty connection that could leak to issues in the future. Recommend saw cutting and jackhammering inside unit in order to expose issue and perform repair Removed wood base in utility closet where AC unit is in order to access drains as well as removed concrete in front of closet. Exposed previous repairs other plumber had performed and removed damaged section of pipe. Found large amounts of cement like sediment inside of drains. Cleaned out sediment and plumbed in new section with proper fittings and pipe.