Sorry, had to provide this info in the first post.
The actual display is marked TM12864G3CCWGWA on the cable and it has 128x64 pixels resolution.
It is a part of how they call it "display card" from Ariterm 901941, which connects to the Ariterm control board 901940.
Both of these parts control the pellet boiler Ariterm Biomatic+ 20. The burner is Ariterm BeQuem 20.
The "display card" Ariterm 901941 is suitable for boiler Ariterm Biomatic+ 20 in combination with Ariterm control board 901940 or directly for Ariterm BeQuem 20 pellet burner with Ariterm control board 901943 (in this case it is installed directly on the burner, and burner can be installed in different boilers).
Image of the "display card":
Image of the control board:
They are connected with 10pin IDC cable.
To emulate the button press, I am using 4 channel 5V relay sending pulse signals to push button contacts.
My wish is to make virtual display and I'm still looking for the solution to capture graphical data.
So I see two ways:
1. Capture video signal sent to display.
2. Try to intercept the signals being sent to the display's driver (capturing signals at 10pin cable end).
It is also possible to connect Radiolink gsm-a2 module from Hellmertz (pdf attached), so there might be also different way to obtain data.