My heating unit makes a loud sound

I’m a little embarrassed to tell this next story, but I’m just going to say it. I mean, it’s not entirely my fault that I didn’t do more research and actually know. But I think the reason is that I have not spent enough time around radiators, or maybe there simply aren’t enough radiators still in operation for me to have experienced their unique system of heating in homes! Either way, I can tell you that I was quite confused with the particular sound of a working radiator during the middle of a cold winter evening, and frankly, the thing scared the crap out of me. I was staying at my friend Anna’s home out in the middle of a field, and the weather outside was quite dreadful! There was chilly air whipping in every direction possible and there was snow blowing off all the tall buildings. I cozied up on her couch and passed out immediately because I was so comfortable. Before I fell asleep I thought I would sleep restfully through the rest of the evening separate from any problems that I may experience, and I was wrong. I woke up a few minutes later, alone in the dark apartment, and hearing something strange. It sounded as though someone was in the room with me, just occasionally making the slightest noise. I couldn’t figure out who would be in there with me, unless it was a burglar, of course. But at no point did it occur to me that the radiating heat I felt must have been coming from somewhere in the room. And I never realized that there were no air vents present in the room, however really hot air was filling the area anyways. It was not until I almost went and disturbed my friend from her sleep to declare that there was an intruder when I looked over and realized that I was sleeping right next to an outdated creaky radiator that was making all of that noise.

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