I have a Lennox N. gas furnace in my home in Peel region. Its on its 22nd year and has worked perfect since. Last week, it failed to start so i called a local technician to fix. After listening to a sales pitch recommending getting a new furnace install, I had my furnace fixed by replacing a minor but expensive part. After inspecting my furnace, I doesn't look like its in too bad condition, the burners look good and most all components look clean. Is there an expire date on these, or can I expect to a few more years use out of this furnace?