Inspectors spent hours at the hotel Monday looking into what happened.
Carbon Monoxide is a colorless, odorless gas that is potentially deadly.
Inspectors were going floor-by-floor Monday looking at the hotel caused 200 people to be evacuated and nearly 30 sent to the hospital.
"The building currently is going to be shut down to all occupancies for unsafe equipment and off limits to all occupancies until further notice," Dunmore borough manager Vito Ruggiero said.
A sign on the door of the hotel indicates it will be closed for only 72 hours but borough leaders say it could be much longer. They found "numerous" other violations including electrical issues.
"Over the years, these places get different maintenance guys and they all have their own means of doing things whether they're right or wrong, they do them," inspector William Fiorini said.
An acting manager at the Best Western Hotel talked with Eyewitness News off-camera. She says the hotel is committed to fixing the issues and reopening as soon as possible.
Roughly 200 people were evacuated from the hotel early Sunday morning after a carbon monoxide gas filled the hotel.
Officials say no working CO Detectors were found on the property.
As for the reason why it happened, Ruggiero said, "the initial findings was a faulty pool heater that wasn't vented properly."
What may be more disturbing is because of the size of the property, it could have taken some time for the gas to build-up.
"It could have been a few days or more," Fiorini said. "The pipe was damaged for a period of time."
Almost all of the people taken to the hospital Sunday have been treated and released from local hospitals.
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