A circuit diagram or the make

[Deelta]

Hi, today I came across a boiler I haven't seen before, it is a commercial type, its big and has two burners, gas valves and control thermostats, the paper in the boiler got the following:
DTG 300-B
2 Allures 7a 8EL
Code 948 60 591 C
any idea what boiler is it and a wiring diagram will help as it has got a complicated wiring behind the front panel, by the way the paper printed I think in German language.

 

[D_Hailsham]

Did a Google and found this:

http://www.dedietrich-heating.com/


They use DTG for boiler names.