If you have a written lease for the rental that you have, you need to carefully read it in that its terms and conditions control the obligations owed to you by the landlord and vice versa in the absence of conflicting state law. You need to read all provisions concerning maintenance of the rental and whose obligation it is to do so and repair it within a state time period.I suggest that you immediately write your landlord a letter stating the problems with your rental requesting repairs by a stated date and if not done by that date, you will hire someone to make the repairs and deduct the costs of repairs from your next month's renatl payment. Keep a copy of this letter for future need.In the alternative, you can request a reduction of your rent from your landlord but that does not solve the fixing of the air conditioning unit.Good luck.