A CL605 Captain reported smoke in the cabin during engine start at the gate from a faulty pack. Engine was shut down and the passenger and Flight Attendant exited the aircraft.

Narrative

While starting our right engine we received a cautionary message indicating that our left PACK had exceeded its limitation regarding max temperature. In addition to the caution message; a burning odor was observed and a visible 'haze' filled the cockpit and cabin. Immediate action was taken by myself and my co-pilot. I immediately shut down the right engine and instructed our flight attendant to open the main cabin door. A few seconds later; when it became apparent that the smoky haze was not dissipating; I instructed our flight attendant to egress the aircraft with our passenger. Meanwhile; my co-pilot was performing the appropriate checklist. He also notified Tower of our predicament by informing them that we 'had smoke in the cabin.' He requested the emergency equipment which promptly arrived a few minutes later. After the tower was notified; we utilized our normal checklists to shut down and secure the aircraft. At this point in time; the smoke began to dissipate. Upon inspection; there was no fire and no damage to the aircraft. A faulty PACK valve was the cause of the overheat condition.Thanks to good teamwork; quick reaction time; and adherence to company procedures; the situation was resolved in a safe and timely manner. There were no injuries to our passenger or amongst our crew. This occurrence proved to be another valuable learning experience and a good exercise in teamwork and crew resource management.