If air cannot flow across the evaporator coil which is part of your air conditioning system and normally located inside your indoor unit. Cool air will not be produced! It must be free from debris, dust, dirt, hair and other contaminates. Take a look at the...
The attached picture is of flex duct piping for a central heating and cooling system installed 25 years ago. As you can see the insulation that is to insure the heated or cooled air arrives efficiently to the room or rooms it is to heat or cool has lost it's ability...