I didn’t used to be conscientious about keeping up with gas furnace maintenance, i’d forget to replace air filters & go various years without scheduling professional service, but for the most part, the oil furnace was honestly reliable, then as long as it continued to operate, I didn’t spend money it much attention, however the gas furnace was about several years old when it quit during the middle of the evening. It happened toward the end of December, during a recognizably nasty blizzard, because the outside temperature was down to drawback twenty-five degrees, both of us couldn’t go without heat until morning. I had problems about the water pipes frigid, bursting & causing extensive disfigure. I had no choice but to call for emergency overtime repairs. The extra fees involved were significant… When the professional accessed the inner workings of the gas furnace, he found a considerable accumulation of dust & other debris on the components! He said that this buildup had diminished airflow & forced the oil furnace to run more often & for longer cycles. He explained that it was much harder for the gas furnace to meet the demands of the temperature control, & that it certainly was required to use more energy, then my heating bills were far higher than necessary for months or even years. I can only imagine what that cost me… Plus, my neglect of the gas furnace had caused enough disfigure to the various parts, it wasn’t worth fixing. I should have been able to get another five or ten years out of the system. Instead, I ended up paying to have a brand new gas furnace installed. I have been diligent about seasonal maintenance & filter swings for the new heating unit.