Sandy Berger The ventilation unit on the roof of IHOP.

Out of the bacon frying pan, into the din of the ventilation unit.

Earlier this month, neighbors of the IHOP on East 14th Street were thrilled when the smell of bacon was greatly reduced by a new ventilator unit on the roof of the restaurant. But the elation quickly gave way to frustration as they realized that the odor-eater causes an around-the-clock ruckus.

“It looks like a locomotive and sounds like a locomotive,” said Sandy Berger, who documented her life as an IHOP neighbor in The Bacon Diaries.

Greta Minsky, who lives on the ground floor in the same building as Ms. Berger, described the sound as a “constant roar” and an “inescapable blare,” adding, “All of us on the first back-floor have little gardens. Forget about sitting out there, if it were cool enough. You can’t hear yourself think.”

At least four others at 230 East 15th Street, which overlooks the restaurant, have also been bothered by the noise that sounded like a steady whir during a phone conversation this morning. Workers apparently completed installing the contraption on Friday, according to Ms. Berger.

The owner of the IHOP, Ed Scannapieco, confirmed that the new equipment was in place. He had heard one complaint regarding noise over the weekend, and said that there “may need to be an adjustment” of the machinery. “The entire exhaust assembly was removed and replaced,” he said, adding that the new system has a decibel-rating 60 percent lower than the previous equipment.

The new fans, motors, and ventilation unit also required the installation of additional transformers, meaning that the final bill will be in excess of the initial estimate of $40,000.

“I did what I said what I was going to do. I wanted to be a good neighbor, that’s what I did,” said Mr. Scannapieco. “There was no law compelling us to do it, but I wanted to do the right thing and we did it. It wasn’t the convenient thing or the inexpensive thing.”

Daniel Maurer

But for now, neighbors are as frustrated as ever and mystified by how the ventilation unit functions. At times a less-pungent bacon smell still lingers. Yet the contraption whirs at all hours.

“I don’t know whether this system is predicated on the fact that in order to get rid of the odor you have to increase the noise,” Ms. Berger said. “It’s a win-lose situation, which doesn’t make any of us happy.”

Neighbors say they have filed complaints with the Department of Environmental Protection, though none have yet appeared online. “I wish I could be like the guy in ‘Network’: ‘I’m mad as hell and not going to take it anymore!'” Ms. Minsky joked. “But I will just be a good, meek citizen and hope that D.E.P. responds and that IHOP responds as a good corporate citizen.”

Ms. Berger was not so optimistic. “After nearly a year of living with them as our neighbors, all we’ve had are problems,” she said.

Even the installation of the ventilation unit caused irritation. “They started working at 6 a.m. I yelled at them and said, ‘You can’t do this at 6 a.m. This is against the law.'”

Their response? “One of the workers, maybe a foreman, yelled back at me — I could barely hear him — ‘We’re doing this for you.'”

Editor’s Note: An earlier version of this post referred to the ventilation unit as a “smog-hog.” That reference has been deleted since the term is a brand name and Smog Hog says that it did not manufacture the unit in question.