Follow CBSMIAMI.COM: Facebook | Twitter

FORT LAUDERDALE (CBSMiami) — Fort Lauderdale firefighters are crediting a neighbor’s carbon monoxide detector with saving a man’s life.

READ MORE: 3 Children Injured In NW Miami-Dade Crash

It was just after midnight Friday morning when David Masters’ carbon monoxide detector started beeping.

“I started smelling gas and I thought I was just imagining it,” Masters told CBS4’s Carey Codd.

CLICK HERE To Watch Carey Codd’s Report 

But the carbon monoxide detector kept beeping so he asked his roommates what to do.

“They were like, ‘Ah, it’s probably just a dead battery or something,'” he said. “They weren’t like in a rush or anything.”

But Masters wanted to investigate so he went outside and put his ear up to his neighbor’s garage. He heard a car engine running and called 911. Paramedics arrived quickly, he said, and busted into the neighbor’s townhouse and found him unconscious upstairs. They rushed the victim to the hospital where he was treated and released.

“I don’t know how long it would have taken to hit us,” Masters said.

READ MORE: Miami-Dade Residents Gather To Protest Closure Of Matheson Hammock Park's West Entrance

Masters said it was a fluke that he even had a carbon monoxide detector and that he only bought it because of a comment a roommate made about his lack of video game playing skills.

“He made some joke like, “‘You’re not doing too well. It must be like…your room’s so close to the garage you must be like messed up on carbon monoxide or something.'”

So he went and bought two detectors. Fort Lauderdale Deputy Fire Chief Timothy Heiser is glad he did and he hopes others do, too.

“It’s a tasteless, odorless, colorless gas and without a detector to warn there’s no way to warn you that your house is filling up with this poison,” Heiser said.

That’s what happened in Wilton Manors earlier this month when investigators said carbon monoxide poisoning killed Louis Agro and sent his wife and 11-year old daughter to the hospital. The family apparently left their car running in the their garage after returning home from a vacation.

Masters feels fortunate that the detector helped save his neighbor, himself and his roommates. He said it was worth every penny.

“Highly recommend,” he said. “Worth that $20. Definitely glad that I did it.”

MORE NEWS: RNC Donors Gather To Hear Trump, Others In Palm Beach, The GOP's 'New Political Power Center'

A man who answered the door at the victim’s house said the victim is home from the hospital. The man said the victim was driving a car that was unfamiliar to him and it starts without a key. The man apparently thought he turned the car off but he hadn’t.The victim has expressed his gratitude to his neighbor.