When my wife and I moved into a brand new house, it was new to us but the house itself was actually pretty old.
We had just settled in and were starting to move some of the furniture into the house when we noticed that the house felt pretty hot.
My wife then offered to go and turn on the air conditioning system. When she went over to the thermostat that was on the wall and turned on the AC, a bunch of dust came pouring out of the vents. It comes to both of us to start coughing and sneezing as the dust falls into our eyes and nose onto our faces. Needless to say it was completely unexpected, that we had a problem right away and the problem was that we had very filthy ductwork. After talking to my wife we both agreed that it would be best to schedule an appointment with a heating and air conditioning professional and he could come out and perform a ductwork cleaning. Wait, we were able to get a heating and AC appointment almost right away and the HVAC technician came out the following Monday. When he came out here he told us that he had never even seen such a large amount of dust, dirt, and debris. It was a huge relief when all of it was clean and said and done. The house felt much cleaner and we can enjoy the heating and cooling system without having to worry about dust floating through the ajr. I might even get a HEPA for extra measure.