Common AC problems
1. Refrigerant leaks
If there is lack of refrigerant in the system there are only two possible reasons either it was under charged during installation or there is a refrigerant in your system.
If there is refrigerant leak than adding the refrigerant is not the solution you must call a professional to find out and fix the leak.
2. Drainage problems
If the condensate pipe outside the house is not draining problem then it might be clogged mount your drain lines at the proper level to stop them from being clogged.
3. Poor compressor
If the air filters are not change regularly they reduce the air flow in the system. Reduce air flow affects the working of compressor and the fan present in the unit. They might even stop working. Repairing work by a professional will be required to repair your compressor.
4. AC blowing warm air
If your air conditioner is blowing warm air there is chance that air filters are dirty and is not allowing the cold air to enter inside the ducts.
Check the outdoor unit it might have been blocked by leaves, dirt or other particles, system blowing hot air is also the sign of lack of refrigerant call a professional to look after the problem.