I had freon put in my central air conditioner it worked for a week or so but now is not cooling is there away to check for leak

i had freon put in my central air conditioner it worked for a week or so but now is not cooling is there away to check for leak

A good indicator of a refrigerant leak is oil residue around the leak since refrigerant mixes with the compressor oil and travels throughout the system. Also a good grade of liquid soap applied to a suspected leak area will sometimes cause bubbles in that leak area if a leak is present. Otherwise you will need some special leak detector equipment.