Here are some more disturbing findings coming out of the investigation of the Boone, N.C., hotel where three guests apparently succumbed to carbon monoxide poisoning and died.

The Charlotte Observer reported Sunday that the Best Western hotel didn’t put in carbon monoxide detectors — as recommended by an instruction manual — when it installed a pool heater believed to have been the source of the lethal gas.

Best Western Plus Blue Ridge Plaza, run by Appalachian Hospitality Management, had transferred that heater out of another hotel operated by the company, a Sleep Inn, in 2011, the Observer reported. The move of that heater, by the way, was done without any permit or inspection, which the newspaper said was an apparent violation of North Carolina’s building code.

Here is the rundown in this series of errors by the hotel and public officials that apparently led to three innocent victims losing their lives.

In April an elderly married couple, Daryl and Shirley Jenkins, died in room 225 of the Best Western. Despite the suspicious nature of their deaths, local fire officials never tested for carbon monoxide at the scene, according to the Observer.

The county medical examiner didn’t deign to come to the hotel room, nor did he ask for a toxicology test on Mrs. Jenkins to be expedited. That report ended up being sent to the ME a week before room 225 had claimed a third victim, 11-year-old Jeffrey Williams. The report said that Mrs. Jenkins had deadly levels of CO in her blood.

Nonetheless room 225, located directly above the hotel pool, remained in use.  And Williams died. The ME has since resigned.

The Observer obtained a copy of the owner’s manual for the Jandy Lite 2 pool heater that the Best Western moved from the Sleep Inn. Its first page “strongly recommends” that carbon monoxide detectors be installed near the heater when it is used for an indoor pool, the paper reported.

The manual also warns that faulty installation of the heater can cause death or severe injury from carbon monoxide poisoning, according to the Observer.

And here’s another little twist in the case. The Best Western had a contractor convert fireplaces in the rooms that had them, which included 225, to natural gas. As part of that process, the contractor was supposed to install carbon monoxide detectors in rooms that had undergone the conversion. Instead, the contractor mistakenly put in alarms that detected combustible gas, the Observer said, not CO.

Needless to say, a carbon monoxide alarm in room 225 would have saved several lives.

Thankfully, the three victims have not died in vain. Last month the North Carolina General Assembly passed legislation that mandates that hotels put in CO detectors in enclosed spaces that have that a fossil-fuel-burning appliance, heater or fireplace, as well as in hotel rooms that share a floor, wall or ceiling with such spaces, the Observer reported.

That law goes into effect in October.

You run a hotel where an elderly married couple died several months ago, and toxicology reports are still pending on their deaths. But carbon monoxide poisoning is suspected. Yet you rent out that same room where they died, and an 11-year-old dies there this weekend.

You can’t make this stuff up.

In Boone, N.C., Jeffrey Lee Williams of Rock Hill died Saturday at the local Best Western. He had been exposed to carbon monoxide, and an autopsy determined that he died of asphyxiation, according to WCNC. His mother Jeannie, 49, was hospitalized and woke up from a coma Sunday.

The Best Western was evacuated Saturday in the wake of Willis’s death.

Williams was found dead in the same room where the bodies of Daryl and Shirley Jenkins were discovered in April, according to WCNC. Toxicology results on the Jenkins were just released, and confirmed that they perished from carbon monoxide poisoning.

According to WCNC, the Best Western had been ordered to address a ventilation problem in an equipment room by a local inspector prior to all three deaths at the hotel. Officials wouldn’t comment on whether the violation had been fixed.

The room where everyone died is directly above an equipment room that had a natural gas heater for an enclosed indoor pool.