A Brooklyn firefighter who jumped out a window to escape the inferno that killed Bravest comrade Timothy Klein fought back tears as he left the hospital Tuesday.

More than 100 FDNY members applauded as Robert Velazquez, who suffered two broken arms battling the three-alarm Canarsie house blaze Sunday that killed Klein and a 21-year-old autistic man, was wheeled out of Brookdale Hospital.

“His wife never left his side in the ICU,” a nurse told The Post of Velasquez.

The firefighter barely escaped the flames at 10826 Avenue N when the home’s second floor collapsed during the afternoon horror, officials said.

Velazquez and two other smoke-eaters leaped out second-story windows, but Klein, 31, could not get out in time and became trapped under the rubble. He was later pronounced dead at the Brooklyn hospital.

“The whole place was in flames, and he got trapped,” an FDNY source said of Klein, the son of a retired Bravest. “[Klein] was trapped for 20 minutes. Eventually, rescue got him. Heavy, heavy, heavy fire.”

The source said another firefighter ran out of the house engulfed in flames.

“He was just smoldering,” the source said. “He was half on fire.”

Klein, also the nephew and cousin of current and retired Big Apple firefighters, had been on the job for six years and was assigned to Ladder Co. 170 in Canarsie when he was killed.

His parents, Patrick and Diane Klein, and their three daughters were at a solemn bunting ceremony outside the firehouse Monday, where the flag flew at half-staff.

The firefighter’s funeral is scheduled for Friday.

Also killed in the fire was Carlos Richards, an autistic man who lived in the building.