Most furnaces are built to last between 15 and 20 years with proper care and regular maintenance. Gas furnaces tend to be on the longer end of that range, while some electric systems may show wear a bit earlier depending on how hard they have had to work. In a climate like Tyler, where humidity levels stay elevated for much of the year, that moisture can gradually affect components like heat exchangers, burners, and electrical connections. Keeping up with annual maintenance helps, but there comes a point where replacing the unit is simply the more practical and cost-effective decision.