COEUR d'ALENE — Heating, ventilation and air conditioning issues that have plagued Coeur d'Alene High School for a decade have been fixed, and just in time for the start of another school year.

"The system has been giving us problems for at least the past 10 years with a significant increase in problems over the last five years," Coeur d'Alene School District Operations Director Jeff Voeller said. "Last winter, the units would go out when the temperatures were in the single digits and require maintenance to repair and restart, often being down for a week or so at a time. When a unit would go down, all seven classrooms were impacted. Some classes had to go to alternate locations and some used space heaters to maintain minimal heat. Many parts on the units were obsolete."

Graham Construction and Management Superintendent Jeremy Sogge and project manager Joey Dickinson led the 11-week charge over the summer break.

This was no small job.

The work consisted of a roof replacement/overlay of thermoplastic polyolefin over 50,000 square feet. They removed seven large air handler units that fed the 50,000-square-foot classroom and corridor space inside the school. They temporarily removed acoustical ceiling tiles and grid, pulled down 25,000 square feet of ceiling insulation to access half the space and re-installed it before putting the ceiling grid and tiles back in. They re-routed and ducted 35 new individual rooftop units to service the classrooms and corridors and added a new transformer on the roof that allows individual control of each individual rooftop unit.

The end project value, which came in under budget, was $2,932,810. About $300,000 of the project funds came from the district's 2017 bond for design work and the rest was funded through the federal Elementary and Secondary School Emergency Relief Fund program.

Voeller said the HVAC system at CHS was originally installed in 1994 and consisted of seven multi-zone units, each serving six or seven zones per system. This means each unit served six or seven classrooms, rooms or zones such has hallways, he said.

"The school has needed this for a long time," Dickinson said.

Voeller said the upgrade to having individual control for each classroom will improve efficiency, airflow and temperature control.

"If a unit has a problem, it only impacts one room while we make repairs," he said.