ALWAYS ensure that there is full free air circulating around the outer casing of the machine, and that the louvres are unobstructed.
ALWAYS use a proper welding face shield or helmet, with suitable filter lenses. Proper gloves and working clothes should be worn at all times.
ALWAYS remove all flammable materials from the welding area.
NEVER remove any of the panels unless the machine is disconnected from the supply, AND never use the machine with any of the panels removed.
NEVER attempt any electrical or mechanical repair unless your are a qualified technician