Between 20 and 40 employees and patients were removed from the Whitehorse Health Centre on Quartz Road this morning due to a furnace problem that sent smoke drifting through the air ducts.

Whitehorse Fire Department platoon chief Morely MacKay said a “furnace malfunction” released excessive smoke outside the building through the chimney.

Wind from the north then blew the emissions toward the fresh air intake on the structure’s south side.

“It was over-fuelling and not firing up,” MacKay said of the building heater.

“It was blowing smoke out and it was coming into the fresh air intake and filling the building with carbon monoxide and unburned gases.”

MacKay said the toxic fumes “didn’t get to high levels,” though a suspicious smell and subsequent nausea prompted evacuation after a call from occupants shortly before 8:30 a.m.

“They were feeling nauseous, that’s why we evacuated the building,” he noted.

“If their igniter is worn out or the sensor isn’t working properly, (the furnace) will try to fire up or it will over-fuel for a mechanical issue,” he explained.

“You don’t get a proper burn and the exhaust coming out of the chimney wasn’t good.”

Maintenance workers repaired the malfunction this morning, he added.

The health centre offers flu shots and immunization to patients, among other services.

It is located along the Yukon River at 9010 Quartz Rd.

A flu clinic was in session when the evacuation occurred this morning, MacKay said.

Evacuees gathered at a nearby “muster point,” with an ambulance crew on hand to examine anyone with lingering symptoms, though no one was seriously ill, the platoon chief said.

“If people feel nauseous and their CO alarm is going off, give us a call because better safe than sorry.”

MacKay also recommended building occupants check their carbon monoxide detectors monthly using the test button.