WINCHENDON – Following an unexpected week off, Murdock Middle/High School students are back in the classroom – but not in the rooms that they normally occupy.

Beginning on Dec. 4, middle schoolers were bused to Elm Street School in Gardner, while high school students had classes in the basement at Cornerstone Church in Winchendon. Elm Street houses the Gardner Academy and district offices, but the Winchendon students will occupy the vacant third floor.

Murdock was closed all of last week after the building’s hot water boiler malfunctioned Thanksgiving Day, filling the school with soot and carbon monoxide. According to a statement from interim Superintendent Ruth Petruno-Goguen, the cause of the malfunction – described by some as “an explosion” – is under investigation by the school district’s insurance company.

The problem was discovered the morning of Thanksgiving when Director of Facilities Brian Croteau opened the school for the Murdock varsity football team to suit up for the traditional Thanksgiving Day game against Narragansett while conducting the daily building fire check.

According to the superintendent’s release, Croteau has been working with Johnson Controls International to secure replacement parts for the school’s fire alarm panel, which was destroyed by a lightning strike in August. Since then, mandatory routine fire checks have been done at the Murdock School. Parts of the panel were deemed non-reparable and due to supply chain issues, replacement parts have not yet been delivered.

Petruno-Goguen said in her statement that upon discovering the problem, Croteau “immediately shut down the building, contacted all local fire stations, and called the insurance company to assist with the assessment of the situation at hand. Servicemaster began an extensive cleanup process on Friday (after Thanksgiving), and have been working diligently since then.”

According to the release, 6,000 square feet of ceiling are being replaced and the 240,000 square -foot school is being scrubbed down.

“Most of the damage,” the statement continued, “was in the middle school and the gymnasium…Before the school is deemed safe for students and staff to return a licensed environmental hygienist will take air quality samples and these samples will be tested at a certified lab.”

A request to transition to remote learning was denied by Commissioner of Education Jeffrey Riley, according to the statement.

“The students’ daily schedule will be modified and students, staff, and families have been informed of the details,” Petruno-Goguen’s statement read. “We appreciate everyone’s patience and understanding as we maneuver through this unexpected crisis.”

Greg Vine can be reached at gvineadn@gmail.com.