I just bought a new ground floor apartment- because this building was under construction when i closed..I didn't realize there is an extremely noisy hvac unit servicing the building directly behind me. The hvac sits at ground level and someone mentioned to me that they felt the placement was maybe a dob violation...that all large units had to be located on the roof. I was hoping someone could give me some insight as to whether this is a DOB violation. I believe the bldg behind me installed this hvac within the last couple of years, during the construction of my building. I live in a landmark section of Tribeca.