We just moved into a top floor apartment, but we soon discovered that there's a very loud HVAC unit directly above us on the rooftop. We alerted the management, who looked into it for a few days, but they came back and said it was functioning properly and the noise was unfortunately part of the "consistent air filtration system" for our floor level. I walked up to the roof top and stood next to the unit in question (it's a large one; the maintenance guy told me it's like 50 tons -- though I know nothing about HVACs). It's indeed loud, but they do have a concrete wall surrounding it. It puts out a very inconsistent hum and vibration though, which is really the problem. I walked over to the other one on the other side of the roof, and it put out a more consistent hum. Neither was necessarily louder than the other, but the one above us definitely had an intermittent nature to its loudest times -- which of course hits our apartment like a neighbor whose sub woofer is too loud.
The only catch is that our furniture has not arrived yet, so we're living in a mostly empty apartment. Air mattress, few boxes and bags here and there, and a lot of open space. I've read that adding furniture and wall hangings will dampen noise, but since it's coming from the roof (and it's a vibration/deep humming sound), I'm not sure if having the couch and chair, full bed and mattress, etc., will do anything. If the noise is coming from above us, and we're not putting anything between us and the ceiling, we won't be reducing the noise, right? Or am I totally misunderstanding how this all works?
We've thought about relocating to another unit in the building, but we really like this particular apartment, and truth be told, if adding furniture and pictures to the walls is known to reduce this kind of noise, then we might just see how that plays out. But if it doesn't, we don't want to move all of our things in here and then have to move them to another unit; would rather just move everything into the new place and not fuss with it.
Just looking for some options in case the management doesn't want to do anything more about it (we have a meeting with them tomorrow, after an outside HVAC specialist looks at it). We don't have the ability to rip up walls or create new ceilings or any other sort of construction work relating to the drywall, windows, etc., that so many people suggest altering in this situation. Any advice that you can provide regarding ways to add things to one's apartment to reduce this kind of noise would be greatly appreciated, and thanks so much for your time.