Police investigating whether carbon monoxide caused woman's death in Borough Park, Brooklyn

BOROUGH PARK (WABC) -- Police are trying to figure out if carbon monoxide fumes caused a woman's death in Brooklyn.

Nilda Sing's brother, Jimmy found her dead in their Borough Park apartment on Sunday.

Officials are investigating whether a faulty boiler in the basement caused her death.

Jimmy took Eyewitness News to the exact spot where he found Nilda dead on the floor in her bedroom. So far, all indications are that carbon monoxide killed the 55-year-old.

"If you see from basement up, there's no insulation, no nothing," said Jimmy.

Jimmy came home from work to find his wife Maoly and sister, Nilda asleep in the ground floor apartment, where there has never been a carbon monoxide detector.

Jimmy finally reached Maoly, who opened the front door and discovered Nilda dead in her room.

Eyewitness News spoke with the couple as they got home from the hospital - they had been there all Saturday, suffering from carbon monoxide poisoning.

"They found something like a level 5 in my blood, so they had to give me treatment with oxygen sulfur,"

As for the boiler, the super says it was fixed just two weeks ago, a job Jimmy, who's an HVAC technician, says was done incorrectly and not up to code.

"The duct work itself, the exhaust pipe, the flu pipe doesn't have one screw on it," says Jimmy, "all they put was aluminum tape on it, it wasn't suspended it wasn't secured, nothing like that."

An initial autopsy was inconclusive and further testing is needed to determine Nilda's cause of death.

Eyewitness News reached out to the building manager and the company that worked on the boiler, but have not heard back.