Several names often come up in discussions about durable, reliable furnaces. Trane, for example, is usually mentioned. Carrier is another that frequently receives good marks. Lennox tends to be a third brand that is often praised for producing long-lived, reliable furnaces. Those three, along with Rheem, seem to be the brands that generally are found when seeking a durable furnace. That said, the life of any given furnace also has a lot to do with how well it is maintained, how it is installed, and how it is used—all in the context of what kind of environment the furnace is in.