This post is quite old, but I believe the informations I'm providing could be useful to other forum members.
I have a Lukey 902 as well, and as far as I know it's a combination of two other products, the hot air station 850+ and the soldering station 936A (not sure about this last product number, anyway).
Some year ago my air gun fell on the floor, killing the heating resistor and some other components on the PCB. I bought the heating element from a web store that provided me with the schematic diagram, and with it I was able to fix my station.