Gov. Rick Scott announced that the Florida Department of Children & Families and the Agency for Health Care Administration have begun an investigation.
But officials said they are anxious a new crisis could emerge when homeowners find their neighborhoods have no fuel, power, running water and other basic services.
Florida Health Care Association, which represents 81% of Florida's nursing centers - but not the Rehabilitation Center at Hollywood Hills - said about 150 facilities out of almost 700 nursing facilities in the state do not have full power services restored.
There are now no patients at the center.
Before the incident in Hollywood, the number of U.S. deaths was 13. But it's under intense scrutiny amid calls for more accountability.
The nursing home was bought at a bankruptcy auction two years ago after its previous owner went to prison for Medicare fraud, according to news reports at the time of the sale. The generator is a large 15,000-watt model that's capable of powering an air conditioner.
How many staff members stayed at the facility - and did that number include doctors? More than 150 people were evacuated, many suffering from respiratory issues, dehydration and heat-related problems, according to Memorial Regional Hospital spokesman Randy Katz.
"There is no doubt that we have become better", said Brian Wolshon, a specialist in population protection at Louisiana State University.
Hollywood police carried out a search warrant of the Hollywood Hills home as the criminal investigation into this tragedy moves forward.
The state has also made urgent efforts to protect its vulnerable elderly residents after a string of home deaths at a nursing home.
"The suspicion is that these deaths should not have occurred", NPR's Jon Hamilton reported from the scene Wednesday. After the air conditioning went down, staff set up "mobile cooling units and fans to cool the facility", Carballo said.
The center had a generator on standby "in compliance with state regulations", as well as seven days of food, water, ice and other supplies, including gas for the generator, Carballo added.
Governor Scott said Wednesday he was "absolutely heartbroken" to learn of the "unfathomable" deaths at the retirement facility and promised to "aggressively demand answers".
Early Wednesday morning, three patients arrived at the hospital across the street with extremely high body temperatures.
While Sanchez declined to say what the temperatures were on the second floor of the building, the deaths illustrate the perils that can persist and even increase in the aftermath of a major disaster for the elderly and medically fragile. The state lists Dr. Jack Michel, of South Miami, as the company's manager.
Police were also checking 42 assisted living facilities and nursing homes in Hollywood. Two-thirds of Lee County's customers and nearly 80 percent of Collier County remains without power, and entire communities remain inundated. "The grid doesn't know business from residential, neighborhood from neighborhood", said Rob Gould, Vice President, Chief Communications Officer of Florida Power and Light.
The ground was already saturated from a nor'easter that pounded the area with rain days before the hurricane struck, so Wolf said it wasn't surprising so many trees were felled when winds from Irma hammered the region.