I have rented a house that has a gaggenau cooktop, and I don't see how to make it work. I also don't see a product number. It is a flat cooktop with a round metal disk that is not attached, but as I understand it is how you operate the stovetop. There are 5 small circles, including an on and a timer, one marked M, one marked A, and one with >> (I am in sweden if that makes a difference). Please advise on operation of this cooktop -