TL;DR
***This unit may have a wiring fault which is incredibly dangerous, potentially deadly, and a fire hazard.***

I was gifted a brand new "858D Hot Air Rework Station" being sold by "Kohree" on Amazon Prime. It is one of the highest rated on Amazon and was positively reviewed by Dave Jones on EEVblog.

858D SMD Rework Station

When plugged into a 110v GFCI outlet for the first time sparks flew out the front panel and the outlet tripped. I plugged it in a second time to record this video.


Something has gone horribly wrong. I called Amazon and they issued a complete refund asking me to throw it in the trash. Lets try to fix it.

It's mostly empty space

There are nasty burn marks around the mounting holes on the rear face of the front panel. Something on the front panel is shorting to ground.

Burn marks

With the front panel no longer grounded, it measured 116v. The entire front panel is wired HOT! This unit will electrocute somebody.

116 volt potential from the front panel to ground

The neutral wire is fused, which is useless since power is shorting from hot to ground. Without the GFCI outlet this rework station would have been destroyed and possibly on fire. GFCI works by comparing the current on the hot and neutral wires; if they're not the same, power is escaping through ground and it shuts off. The fused SHOULD interrupt the HOT wire.

Fuse on netral

Unplugging different connectors on the board lead me to the blower assembly. The short disappeared when the grey/white connector, seen in the "Burn marks" photo, was unplugged.

Blower disassembly

The grey and white wires are the heating element leads. Everything seems alright with the PCB minus a few cold solder joints.

Grey and white wires on the bottom right of the blower PCB

Here is the short. The yellow grounding wire for the nozzle is fused to the heating element.

The short

There is a thin insulating film between the heating element and the metal nozzle. It's not hard to see how the grounding wire could accidentally slip onto the wrong side of the insulation.

The correct assembly

It works!

No more sparks

Here are the burnt screws which attach the front panel to the metal housing.

 

Conclusion

This unit may have a wiring fault which is incredibly dangerous, potentially deadly, and a fire hazard.

There is a ground fault caused by sloppy assembly, the front panel is wired HOT, and the fuse is on neutral. I can't believe my unit made it through any sort of quality control; it would have failed the initial power-up. If you buy one, at least test it on a GFCI outlet.