About two years ago, I realized my furnace needed to be replaced. It was no longer capable of handling the severe winter weather in my area. I noticed much longer run times and much higher monthly utility bills. The house often felt chilly, no matter how high I set the thermostat. The furnace had also begun making some strange sounds, spread quite a bit of dust from the vents, and smelled rather musty whenever it operated. My family often complained of headaches during the winter, and I blamed the furnace. Rather than wait for the heating system to fail during the middle of the winter, I decided to take proactive measures. I started researching what to look for in a new furnace, with the plan to handle the installation process over the summer. I discovered that the different manufacturers and models offer basically the same features. The AFUE ratings vary, along with price, and most top-of-the-line furnaces are equipped with variable-speed operation, stainless steel heat exchangers and zone control capability. The Energy Star rated furnaces tend to be more expensive but save money on heating bills every month. From what I read, the model of furnace is not as important as proper sizing and installation. Some HVAC contractors tend to oversize the furnace because it’s easier than making accurate heating load calculations. Unfortunately, larger furnaces cost more to purchase and won’t provide superior comfort. The system will heat up the space too quickly and never achieve maximum efficiency levels. A furnace that is too small will run continuously and never manage to sustain perfect comfort on super cold days. Whether the furnace is over- or under-sized, it will experience excessive wear and tear and not last as long.