Ray Wohlfarth: Why boilers are still a great heating source

“According to the ASHRAE HVAC Applications Handbook, the estimated life of an air-to-air heat pump or a rooftop unit is 15 years while a boiler life expectancy is between 24-35 years, depending on the boiler type. So, you will install two heat pumps or rooftop units for every boiler. Where do you think those old units will end up?” I ask the class.