The answer to 'best replacement' is to consult with a licensed and experienced HVAC technician to determine the best replacement system for your home. They will assess your home's size, layout, existing ductwork, and energy efficiency needs to recommend the most suitable replacement option. A professional HVAC technician can also provide guidance on energy-efficient models, rebates or incentives, and proper installation to ensure optimal performance and long-term savings.
When considering a replacement, it's important to look at the system's SEER (Seasonal Energy Efficiency Ratio) rating, which measures its cooling efficiency, as well as the AFUE (Annual Fuel Utilization Efficiency) rating for heating efficiency. Newer, high-efficiency models can significantly reduce your energy costs and environmental impact compared to older systems.