This is going to be dumb to you experts but to us mortals it's not a couple of questions on the Recirculation and Wastegate valves

Exactly how and when do they operate ? I know they operate in a different way to the dump valve and thats as far as it it goes.

When does the Wastegate open ? I'm guessing mine is working as I haven't blown the engine up yet
When and how does the Recirculation Valve work ? Again guess mine works