Regrettably, furnaces don’t behave like electronic devices, where they may show signs of malfunction before completely shutting down. Furnaces often fail abruptly, leaving you without heating. To prevent any interruptions in your heating coverage, we strongly recommend adopting a proactive approach by replacing your furnace when it nears the 12-15 year lifespan threshold. It’s crucial to keep in mind that older furnaces can emit carbon monoxide, even at low levels, which can lead to symptoms like headaches and a general feeling of unwellness. By ensuring your furnace is not approaching the end of its life, you can mitigate these mild symptoms as well as more severe ones.