need hp 2210 all--n-one repair manual

The scanner gets stuck on warming up. I have recycled and reset per instructions I find in the forums. Put power into its own outlet. Still freezes. Might work once or twice.

Once it freezes I cannot print a page which is a trick someone recommended to reset it.

I see dirt and smoky deposit under glass, and streaks like scanner head is touching glass?

How do I open this up to clean?

If there is a repair manual please send a link or attach to email. Thanks for any help.