Background

Hi Houzz. I live on the third floor of a four-floor apartment building, wherein the ground floor is a currently-unoccupied commercial space and there are six total residential units in the building. I have a neighboring unit above me, below me, and in front of me. Two of my walls are exterior walls, and the third wall borders the common hallway, which then has its own exterior wall. My utility closet is in my kitchen, and both the utility coset and kitchen share a wall with the neighboring unit in front of mine.

The utility closet houses a stacked washer and dryer, a tankless water heater, a gas furnace, and an air duct. My building is pretty old, but all of the apartment units are brand new renovations with new appliances. I don't know whether the building's pipes and "guts" are brand new too.

The Problem

For months (months!) now, I have heard a "clicking" sound coming from my utility closet. I attached a video to this post so you can hear what it sounds like.

I have had my apartment's maintenance crew in my unit three times to try to find the source of the sound, to no avail. The maintenance crew has removed the cover on the furnace, powered off the furnace, been on the roof of the building, in neighboring apartment units to try to find something that might be causing the sound, and they have found nothing that might be the source. Because of the way the closet is arranged, you can't move anything to get behind the appliances to look from a different angle.

Everyone who has heard the sound thinks it's happening inside of the air duct. One of the maintenance guys suggested it could be water dripping from a leak somewhere, but I just don't think it sounds like water and they found no evidence of a leak anywhere else in the building. If you listen closely, it sounds like *something* is trying to click on but can't actually turn on, so it clicks itself back off. Then tries to click on again, then off. Then again. Then again. As mentioned, I powered off the furnace one day using the thermostat on the wall, and the sound still happened, so I don't think it's coming from the furnace.

The washer and dryer are typically powered off, too, so I don't think it's either of them. It doesn't sound like water dripping, it doesn't sound like a mouse, it doesn't vary at all in its characteristics. It sounds the same each time, leading me to believe it's an appliance of some type, and not one in anyone else's apartment. Also, no one else, according to the building manager, has noticed or complained of this sound in their units.

This sound happens frequently, at random times throughout the entire day, every day. Sometimes it will click once or twice and be done for a while and sometimes it will click repeatedly for minutes. It's not just when my neighbors walk around their apartment, or just when I do laundry, or only when it's windy outside, for example. There is intermittent construction on the ground floor of the building, but the clicking happens during "non-construction hours" too. It doesn't seem to be tied to anything.

I've started to get (slightly) used to the sound, but it's still irritating because it wakes me up at night or I hear it when I'm working from home or trying to watch TV. It's almost like someone lightly poking you in the arm for months on end; it's not totally unbearable until it is. The property management's maintenance crew hasn't been back since the third visit, which was probably more than a month ago now. The actual maintenance guys have been great and seem to be just as confused as I am, but the leasing office actually closed my maintenance request ticket. I asked for it to be reopened because it hasn't been fixed, but it seems like a low priority for them. I've also asked the building manager whether I should have someone from the gas company or Trane come take a look in case it's a dangerous issue, but they said that wouldn't be useful. Plus, I don't think it's my responsibility to try to find a solution or contact outside help to figure this out (is it? Maybe that's a different thread.).

Help me, Houzz!

Anyway, all of this is to say that it seems like I'm on my own with whatever is going on, and at this point I'm about 50 percent annoyed by it, 50 percent curious about what it might be, and 100 percent unequipped to deal with appliances and utility infrastructure. Even as I type this, it's clicking and taunting me and reinforcing the faith I'm putting into the Internet to help me figure out what the fresh hell is that sound!

I'm happy to provide more information or videos with sound of it happening. Me and my friends who are sick of hearing me complain about this are looking forward to hearing what you all come up with! Thank you!