If your outdoor and indoor units are BOTH RUNNING, BUT NOT COOLING, make sure that all windows and doors are closed, your supply and return vents are open - not blocked, and that your air filter is clean. If no problems there, then you should probably turn the air conditioning off and schedule a service call. Below is a list of possible causes:

• Low refrigerant charge;
• Refrigerant flow-related problem - restriction;
• Faulty metering device;
• Poor efficiency- needs cleaning and servicing;
• Bad reversing valve;
• Bad compressor valves;
• Duct leak in unconditioned space.