Just a note- the ol' Weller 8200 generates several kV at the tip when switching the gun on/off or hi/low.
Kills a lot of semiconductors, like a massive ESD hit.
Trick is only have the heat on or off when touching (soldering) the parts. Or ground the tip (secondary).
I wonder if people know to re-torque the tip nuts fairly frequently to give good connections, or the thing never heats up.