It’s possible to have a gas furnace for most or all of your life without thinking too much about how it works. The gas is burned, right? And of course that makes heat. Simple. But there’s actually more to it than that, especially when it comes to the safety mechanisms. You can’t simply breathe the exhaust fumes from combusted gas!
Some components of your furnace make the heating possible, like the gas valve and the pilot light or electronic ignition system. Some components are only there for safety reasons, like the limit switch. Your furnace’s heat exchanger is critical for both providing heat and keeping you safe. Take good care of it, and it will take good care of you! Here’s how.
Isn’t it great to know that whenever you need warmth and comfort in your home during the winter, all you need to do is adjust the thermostat and your furnace just switches on and starts sending heated air through the ductwork into the various rooms of your home?
When your gas furnace doesn’t come on during a cold winter day, that’s a problem. It may be a 
Our short answer to this is, “it’s not a bad idea!”