Stephen Rex Brown Tommy McKean says that the whir of the air conditioning units directly above his apartment is a constant nuisance.

This time of year, the whir of an air conditioning unit is usually reassuring. But for several tenants living at East 13th Street and First Avenue, two industrial-strength air conditioning units on the roof of their building are instead a constant torment.

“It’s like a helicopter hovering overhead all day,” said Tommy McKean, who lives directly below the units on the fifth floor of the building. “For ten minutes, it’s not so bad. But for 24 hours a day it’s awful.”

The pair of large air conditioners, which cool a Dunkin’ Donuts and Hamptons Marketplace on the ground floor, sit near the edge of an air shaft that two residents said amplifies the racket. A ventilator for the market that also is beside the air shaft adds to the alleged cacophony.

“When the windows are open it sounds like a motorcycle when it starts up,” said Dirk Vandenberk, who lives on the fourth floor and has a window opening to the air shaft. “And the ventilator almost sounds like a big pipe organ out of tune.”

The unit cooling Dunkin’ Donuts has been in place for around five years, according to the building’s owner, Chris Verni. The second unit and ventilator were installed around three weeks ago — and that’s when the noise became too much to bear for around 10 tenants in the building, according to an e-mail chain passed along by Mr. McKean.

Mr. McKean even filed a complaint with the Department of Environmental Protection on Wednesday, which is documented on the 311 map. (A spokesman with the Department of Environmental Protection said the agency had not yet received the notice.)

Stephen Rex Brown Mr. McKean’s building at 13th Street and First Avenue.

“They just heave these things on the roof with no consideration for the environmental impact — not to mention the emotional impact,” said Mr. McKean.

Mr. Verni said he had checked out the machines himself, and hadn’t heard anything that would “qualify as being loud to any degree.”

On Wednesday the air conditioning units could be heard from the stairwell on the sixth floor, and were comparable in volume to an idling truck outside of an apartment.

Workers at both Dunkin’ Donuts and Hamptons Market referred all hard-hitting air conditioning-related questions to their managers, who were not available.

Mr. Verni said the heated dispute over the cooling units was in the hands of the inspectors from the Department of Environmental Protection, who would determine whether the business owners were in compliance with noise regulations.

“The tenants should enforce their rights. That sounds like what they’re doing,” Mr. Verni added.