Air Conditioning - cool but not cold

hi, my air conditioning ,which is central air , seem note to cool very well, I had it charge with gas, but that didnt seem to help much, it still doesnt seem to cool the house down, my home is 4 years old, so the unit is like new,. Isnt the unit oppost to cool down alot, like if my house is 90 inside and i turn my unit on to 72 , shouldnt it cool down to the temp. It does it run all the time and doenst seem to cool the home the much. any ideas?

Check the copper piping at the outside unit....when running the large line should be cool and wet and the small line should be warm. If it is as written, the compressor is running...if not you'll have to find out why the compressor is not running..could be a bad capacitor, etc.