The answer to 'how to maintain central air' is to perform regular maintenance and cleaning on your central air conditioning system. This includes cleaning or replacing the air filters, clearing debris from around the outdoor unit, and scheduling annual tune-ups by a professional HVAC technician.
Keeping your central air system well-maintained will help it run more efficiently, reduce energy costs, and extend its lifespan. It's important to follow the manufacturer's recommended maintenance schedule and address any issues promptly to avoid more costly repairs down the line.