Three people, including a firefighter, suffered minor injuries, officials said.
At around 7 a.m., about 70 firefighters rushed to the apex of the Fifth Avenue Trump Tower skyscraper at 57th Street in midtown Manhattan to put out the blaze, fire officials said.
They were met with steam and smoke brought on by the 19-degree conditions, officials said.
Firefighters extinguished the blaze “without any problems within the building,” FDNY Manhattan Borough Commander Roger Sakowich said.
But smoke continued emanating from a rooftop heating and cooling unit of the 58-story building, fire officials said.
At least one firefighter suffered minor injuries after being hit by debris before being transported to the hospital.
Two building employees, including an engineer, were evaluated at the scene for smoke inhalation but refused medical treatment, the officials said.
There were numerous announcements addressing tenants to assure them that there was no need to evacuate because the smoke from the fire hadn't breached the building.
Trump's son Eric Trump tweeted about "a small electrical fire in a cooling tower" on the roof of the building and praised the FDNY for arriving "within minutes and did an incredible job."
"The men and women of the #FDNY are true heroes and deserve our most sincere thanks and praise!"
Trump Tower, named for the 45th president, is also the headquarters of The Trump Organization and was the campaign nerve center for President Donald Trump when he ran on the GOP ticket in the 2016 presidential election.