Kaeser SK19 - Oil change in the compressor - screw compressor

Hello
I bought a Kaeser SK19 compressor, used. I want to change the oil, I bought filters and oil. Unfortunately, I can not find any instructions on the internet. The operation would have seemed simple, if not for the bottom of the drain valve. From what I read it should be at the bottom, which also pollutes. Is there another way to drain the oil. I have all windows and exits like in the picture:

or the big hex on the top of the lid to the oil inlet?

I am asking for help, I have nowhere near the site and nobody knows about compressors.

Thank you and best regards

Here you should find the information you need: http://www.kaeser.pl/Contacts_and_More/Poland_Kaeser_Kompressoren.asp#0

I called Gil Gil, he told me that there must be a trigger down, but he does not have it, just as the filler screw should be red and you can not see it, maybe they have the newer models.

Have you solved the problem with this oil?

If you still have not solved this problem, the trigger is visible in the first picture just below the radiator, there is a valve at the end of which the hose should be but you can see only the nozzle. It is so high because inside there is a tube that runs to the bottom of the tank. You just have to remember that the oil is drained before the pressure is applied to the separator tank and that it does not become vented immediately, the venting valve must be closed. By the way, this machine is very run down, you can see it has already passed. In addition to the oil and air filters, I would advise you to replace the separator cartridge because it has already passed its course and will release huge amounts of oil into the network.