Forced air heating and cooling systems require a lot more work than I originally believed. When I first bought this home, I thought the nice modern HVAC system would be awesome. Finally a place that has central air conditioning as well as central heating. No more obnoxious window AC units or those huge old wall AC units from the 80s which burn through so many kilowatts they’ll run your utility bill through the roof. I followed the instructions from the manufacturer as well as the information from the homeowner’s insurances company, which clearly states we need to both change the air filter at least once a month as well as have the whole HVAC inspected twice a year and by the heating and AC company that the insurance company uses. Well, I did those things, and I was still having trouble with the HVAC system. The parts were running great, but I noticed the whole thing was definitely cycling for much longer than it did when we first bought the house three years ago. At first, I started changing out the AC filters every two weeks. Since I have two dogs, I thought that might be the problem. When that didn’t work, I called the HVAC contractor. Instead of inspecting the HVAC unit, he looked at the ductwork and immediately recommended a cleaning. Even with regular air filter changers, the ductwork he said still needs to be cleaned at least once a year, every year. Without regular air duct cleaning, the system can get really gross, which prohibits airflow and makes the whole system overtax itself.