The answer to 'how to maintain replacement' is to perform regular maintenance and cleaning on your HVAC system. This includes changing air filters, cleaning the condenser coils, and inspecting the system for any issues. It's important to follow the manufacturer's recommended maintenance schedule to ensure your HVAC system runs efficiently and lasts as long as possible.
Regular maintenance not only keeps your system running smoothly, but it can also help prevent more costly repairs down the line. Be sure to turn off power to the unit before performing any maintenance tasks, and consider calling a professional HVAC technician if you're not comfortable with any of the steps.