First off, yes I should have unplugged the unit, that's on me. But I hope this video helps others avoid a potential shock, or even better @MrHeaterTV directs their manufacturer to review this data and hopefully fixes this for future units, maybe even sends customers a safer switch assembly.
EDIT: @MrHeaterTV think this switch may be the cause of your many burning up of motors (exhaust and room blowers)... When this switch is OFF it allows 120V to flow through all of the motors and since the neutral is the fused lead any kind of short to ground will not be protected by the fuse, blow up the transistor on the board. I would prioritize this switch being corrected, and you should consider adding the ground wire to the controller (for the Y-Capacitors that I previously brought to your attention).. I would be willing to bet almost 90% of your failures start to go away after these two minor fixes.