Tin foil was the culprit

So I decided to get a ladder & go up to have a look at the air vents of the central heating & A/C in the residing room

A few years back I was residing in this one beach house I was renting. And every time that the central heating & A/C would come on I would hear this crumpling of paper category sound that was almost prefer a rattling sound. It was driving myself and others nuts forever! I could not figure out why every single time the central heating & A/C would come on that this noise would be going on; Well, one day I finally had enough of it & I wanted to investigate into this. The noise was only coming from the air vents in the residing room. In the home office & other parts of the beach house it was not happening. So I decided to get a ladder & go up to have a look at the air vents of the central heating & A/C in the residing room. The air vents were in vaulted ceilings so I needed the ladder. When I had a deep look into the air vents I found what was going on! There was tin foil in there for some reason. Before I removed this tin foil from the air vents of the central heating & A/C I wanted to check with our landlord first to make sure it wasn’t there for a reason, my landlord did not think why it was there & was surprised himself! So I went back up there, took off the air vent cover & got the tin foil removed from the air vents of the central heating & A/C in the residing room area of the house.

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