Many HVAC issues, regardless of whether you’re using the heating or air conditioning, start with clogged air filters. When too much dust and debris gets sucked into your system and accumulates in the filter, it can severely restrict the system’s ability to force air through it, meaning your system has to work a lot harder to achieve the same results.    This often means it takes more energy for your system to do its basic cooling job when the temperatures start soaring. Changing your furnace filter in the summer can prevent overworking, and many other problems, too.  How Your HVAC Works The most common heating and air conditioning system is called the forced-air system. This uses a heat exchanger to heat or cool incoming air (it does both, don’t be put off by the name) before the air handler forces it out with a fan through your entire home via the supply system of ducts that snake their way through your home. As the cooled air flows throughout your home, the fan o...