The answer to 'how to fix air conditioner' is to first troubleshoot the issue and then perform basic maintenance or repairs. Start by checking the air filter and cleaning or replacing it if it's dirty. Next, inspect the outdoor unit for any debris or obstructions around the coils, and clean them if necessary. You can also check the thermostat settings and ensure the unit is getting power.
If the issue persists, you may need to check the refrigerant levels, clean the condenser coils, or address other more complex problems. However, it's important to note that some air conditioner repairs should be handled by a professional HVAC technician, especially if they involve electrical or refrigerant components.