Ferroli optimax he 38 c filling kit connections?

I topped up the water on my boiler, but think I have moved one or more of the other 3 "taps" that make up the filling kit and wondered if someone can let me know how they should be set - the 1 blue cold water in should be open for the hot water supply, the next black one closed (down) as this fills the ch system, but following black and then blue one I am unsure of! If someone is able to help it would be gladly appreciated for peace of mind!