There are certain things in my life that I am super lazy about. One thing that I am bad about is air filter changes. This came to bite me in the butt the other day. Apparently, the air filter can cause the entire gas furnace system to die. The purpose of an air conditioning filter is to catch dust before it goes into the heating system. The air filter can only catch so much dust though. Eventually it clogs and needs to be changed. Every month the air filter should be replaced with a new one. Well, I was not on it with that HVAC filter change. I let the air filter sit dirty for around three months. My heater then just did not turn on one day. I switched the furnace filter but it did not make a difference. I called a heating business and they sent a guy over. The HVAC contractor was literally disgusted with me. He said that my air filter was too dirty to catch anymore dust for my gas furnace. So the furnace just sucked up the dirt and eventually overheated. When it overheated, the heat exchanger got a crack in it. With a crack in it, the heat exchanger cannot work and the furnace won’t turn on. The price tag on a new heat exchanger is about the same as a new furnace. A new air filter is a couple of bucks. Because I did not get on that air filter, I either need to buy an expensive heating part or a brand new furnace.