Most HVAC systems last 15 to 20 years, though some can stretch further with good maintenance. The signs that replacement is approaching include rising energy bills without a change in habits, uneven temperatures throughout your home, frequent repairs, unusual noises like rattling or squealing, and the system running longer cycles to maintain comfort. If your system is over 15 years old and showing any of these symptoms, it’s worth having a conversation with a professional about your options.
The key is not to wait for a failure.
I learned this the hard way with a hot water heater. I had a 30-year-old unit and spent a couple of years thinking about which high-efficiency replacement would make the most sense. Then, the day before Thanksgiving — with a houseful of guests arriving — the unit failed. I called a local plumber who had the time and a hot water heater in stock, but it was the lowest efficiency model available on the market. I was lucky to get it replaced on such short notice, but it was not the unit I would have chosen. The new one is more efficient than the old because manufacturing standards have improved, but an opportunity was missed.
That experience informed how my wife and I approached our HVAC system. Our furnace was 16 years old and the cooling condenser was 12. The expected life of this equipment is 15 to 20 years, so the timing was right. By planning ahead, we were not replacing a furnace when it was 10°F outside or a cooling condenser when it was 95°F. We had the time to research, compare, and choose the system that best fit our home and our values.
A planned replacement lets you consider what matters most — energy efficiency, long-term costs, resilience, and the consequences of our decisions as they relate to climate change. When you are responding to a breakdown, you are limited to whatever is available that day.
We chose a dual fuel heat pump system with a natural gas furnace for backup. The heat pump carries the majority of our heating and all of our cooling, and the gas furnace provides backup during extended cold stretches or outages. We know that converting as much of our energy use to electric and purchasing renewable energy is the best we can do to help the environment. Our decision also had to consider resilience. As we consider the predicted increase in weather-related power outages, we want to make sure we will not have extended periods without heat. We also have a solar system with battery storage, so if the electricity goes out in summer, the battery keeps the refrigerator going and we open the windows.
This kind of decision takes time and thought. We were able to weigh energy efficiency, resilience, and our desire to minimize our impact on climate change — all because we started the process before anything broke.
When you shop for a new HVAC system, you will see efficiency ratings on every piece of equipment. Since 2023, the U.S. Department of Energy uses updated metrics — SEER2, HSPF2, and AFUE — that better reflect how systems perform in real-world conditions.
SEER2 (Seasonal Energy Efficiency Ratio 2) measures cooling efficiency. It tells you how much cooling, in BTUs, is delivered per kilowatt-hour of electricity over a full season. In Ohio, the current minimum for air conditioners is 13.4 SEER2, and for heat pumps it is 14.3 SEER2. Higher is more efficient.
HSPF2 (Heating Seasonal Performance Factor 2) measures heat pump heating efficiency. It tells you how much heat, in BTUs, is delivered per kilowatt-hour of electricity. The current minimum in Ohio is 7.5 HSPF2. The higher the rating, the less electricity the heat pump uses to heat your home.
AFUE (Annual Fuel Utilization Efficiency) measures furnace efficiency — the ratio of heat produced compared to the energy consumed. A 96% AFUE furnace converts 96 cents of every dollar of fuel into heat.
When comparing systems, ask your contractor about these ratings and look for equipment that exceeds the minimums. Higher-efficiency systems cost more upfront but deliver lower energy bills and a longer return on your investment
Planning ahead and proactively updating your HVAC system is the best route to take. Your decision on which system to buy may differ based on your situation, but I encourage everyone to plan ahead and do the best you can to minimize your impact on climate change.