I moved into a new place in august, and since a few weeks, I started hearing a humming noise after midnight till morning some days. It is not loud; it is a low level low frequency noise, which sounds like an engine or fan running in distance. The problem is when it happens during the silence of the night, the frequency feels like resonating in my brain and keeps me from sleeping, giving me a headache and nausea. I think, it is not tinnitus or "The Hum" , and not construction in the vicinity.
I cannot locate the source; it is all around the house, feels like coming from outside my apartment. It is possibly the heater vibrating the walls, or a ventilator fan in the roof that has gone a bit bad. or, maybe coming from such a source nearby the building.
The landlord is trying to help, by sending an electrician or heating technician. But since this happens some days and during night, or is audible then due to lack of environmental noise, they could only check the heater in the basement, which does have a normal buzzing sound. It would be difficult (or rather not really possible) to call them in after midnight when i start hearing the hum. I tried to record it with a mobile phone, but that is of no use, its microphone only records what sounds like static, does not pick up the low frequency hum.
Does anyone have any suggestion, or experience with a similar situation, that can help me/us identify the source or get it fixed?
My place has a fan in the laundry drying room. Sometimes people leave it on overnight. I'm on the groundfloor and so I can hear it, I've asked a few neighbours to please knock it off before 2300 and all is well now.
If you apartment is built to Minergie standards then the hum will most likely be from the air handling system. if you have air vents in each room, you have an air handling / heat-recovery system somewhere.
thanks for the ideas, i will check with the neighbors. and, hopefully, the technician will check whether there is an issue at the roof.
it does not get louder or better in different rooms, so, i doubt that it is something in the apartment. it seems to happen after midnight.
the house is an old one, and does not have ventilation in each room. only the one in the toilet, which is kinda similar noise, but it is not running after midnight till morning.
if it is the heater in the basement vibrating the walls, or the pipes or something, i am not sure whether they can do anything. noise cancelling headphones, or move to another place, i guess.
I suspect it is the pump of the heating. Or a nearby heat pump https://en.wikipedia.org/wiki/Heat_pump which only works during night when electricity is cheaper.
Before looking at all kind of equipment and buying whatever measurement tools.
When the sound is there, go outside, listen on the street, listen a block away. Be sure it is your building and not something from blocks or even kilometers away, people differ and you might be more sensitive to that sound than the average, low sound travels very far. We once had a complaint from somebody in the neighbourhood of our factory (not in Switzerland) and eventually it was decided that we would do a short 100% all electric of all equipement and cabinets during a rebuild phase and test again. She still heard it, but we were of the hook. More than a year later it turned out to be from another factory kilometers away. And she was the only we ever knew that did hear it.
the thing is, when 'the hum' is there, existence of other sounds make it less disturbing. even when there is some sound from clothes due to simply moving, or some music, temporarily it is not as audible or as disturbing.
as you suggested, one night i left the apartment and went outside to the front of the building. i did not feel the disturbing sound outside, but i could not say whether the sound was there, because of the wind sound blocking it. also, after being exposed to 'the hum' for a while, changing to a new place feels weird due to change in pressure, heat and environment noise, and due to sudden lack of 'the hum'. so, i was not able to do proper mapping of its existence while leaving the apartment. and i was tired due to headache and lack of sleep at around 4 at night
i went to the heater room, and could hear that it was making a similar sound, which is expected, but it was louder and not disturbing and not resonating in my head.
next time, i will try recording with a decibel meter app, on a night with and without, to have a better comparison.
also, i tried the tone generator link from the post listed above. it does produce similar irritating resonance feeling around 50-60 Hz and around 105 Hz. (well, i did a quick test with a small range) i will check the fuse box and switches to be sure.