What is that noise?

I was lost when my husband passed away.  I hadn’t lived alone for over thirty years.  I wasn’t about to give up my home and move in with one of my kids.  I loved them, but I could never live with any of them. I also couldn’t leave my home, where my husband and I had lived since we got married.  I was suddenly no longer hearing his breathing, but I was hearing the sounds of the house, when I was supposed to be sleeping. These were supposedly familiar sounds, but I didn’t remember hearing them before.  I began to imagine all kinds of things happening in the walls when I heard the tapping and ticking. I imagined I was infested with rats. I could hear them chewing in the walls. I could imagine them chewing through the wires.  I could just imagine a fire starting when they chewed through and my house burning down. I had to call the exterminator to get rid of the rodents. When the exterminator told me there weren’t any rodent, I was shocked. He told me that he thought it was a problem with the ductwork.  I called the HVAC company, but I doubted it was the ductwork. When the HVAC tech arrived, he confirmed what the exterminator told me. He said there was clog and what I was hearing was the ductwork expanding and contracting as the airflow was strangled and then released. Once he cleaned the ductwork, the sounds had gone away.  He told me I was lucky that the furnace and air conditioning had not been injured by the clogged ductwork, since it had to have been nearly clogged for the past year.

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