switches on freezer?

I have a priveleg freezer, the size of a small fridge, and it has three lights on it, in order they are: yellow, red & green. There's an "s" and a triangle, that I can turn off and on. I want to understand what all these mean. I can't find a make or model number on it anywhere, or other helpful information - I bought it second hand - and it works fine, but I am not sure what switches I should have on.
Thanks!!
C.Dockery
March 2009