"I was fixing heating contractors mistakes left and right, things that would get people killed," the whistle blowing plumber said.
In talking to Eyewitness News, he requested anonymity for fear of retaliation.
While at Rapid Repairs he documented what he says is shoddy and potentially deadly work such as this faulty boiler flue.
"So the carbon monoxide will," Eyewitness News Investigative reporter Jim Hoffer started to say.
"Spill into the room," the plumber said.
"That sounds very dangerous," Hoffer said.
"Yes it is, it is very dangerous. This will kill someone," the plumber said.
He showed Eyewitness News one out of code installation after another from the dangerous to the dumb.
"The water heater is installed, the flue pipe's installed but there are no water lines coming to it or going from it," the plumber said.
"So this was passed off on?" Hoffer asked.
"This was passed off, this was passed off," the plumber said.
"As completed," Hoffer said.
"As completed and the complaint came back to me was why am I not getting any hot water," the plumber said.
The most absurd was a backward installed gas meter.
"This is the gas register, that's the thing that you read, you couldn't read it with a mirror, it's impossible," the plumber said, "The homeowner's going to get a violation for obstruction of meter, that's what's going to happen."
"How did that pass inspection?" Hoffer said.
"I have no idea," the plumber said.
But it's the unsafe work done by city-hired contractors that keeps him up at night and compelled him to contact the city's Department of Investigation.
"What did you tell them?" Hoffer asked.
"I told them that what was going on was a total sham and there were contractors that shouldn't have been allowed into the program," the plumber said.
The Eyewitness News investigation found he's not the only plumber speaking to city investigators.
"You provided documentation?" Hoffer asked.
John Norton: "Showing I installed the boiler after Hurricane Irene," said John Norton, a certified plumber.
Certified Plumber John Norton says the Department of Investigation called him after a Rapid Repair contractor billed the city for a boiler Norton privately installed more than a year ago.
He says investigators won't have to dig too deep to find problems.
"How many bad rapid repair jobs have you seen?" Hoffer asked.
"So far I looked at about 10 to 13 of them," Norton said.
"I still don't have any heat or hot water," said Salvatore Presti, a homeowner.
Sal Presti got Rapid Repair boiler weeks ago, but they never got it up and running.
Now his pipes have frozen and burst:
"Someone is doing very sloppy job, there is little supervision of what is being done with public money and the result is several months after the hurricane most of this block has no heat or hot water," Presti said.
The Department of Investigation told Eyewitness News late Thursday afternoon that they are investigating several allegations of fraud involving Rapid Repairs.
The Mayor's Office says the program has successfully restored critical services to more than 19,000 residential units at no cost.
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