vacation time...help!

So I will be starting a new job (just got the initial offer from HR, they are just formulating the paperwork and said it will be ready by Friday)--it's a different floor within the same hospital system. So I retain my accumulated vacation days, etc. NOW--on to my question. I have a one week vacation planned for mid-September. This position is 4 10-hour shifts, no weekends. So ultimately, I'd need 4 days off work to cover my 5 day vacation. How do I go about asking for this time off? Do I tell the HR lady when I officially "sign on?" Or do I wait to tell my manager? I honestly have no clue as to how to go about this. At least it isn't prime "summer" vacation time (June, July, or August) but I dont want to go in on a bad foot asking for vacation time already. On the other hand, they have to realize people have a life and I *have* been with this hospital system for several years. I paid for 1/2 my share of the vacation already. Do I suck it up and keep mum, or do I ask for time?

Any thoughts welcomed!
In my system the best thing to do would be to include this time in your contract as a " condition of hire." This is how I got prime summer vacation time off for a honeymoon as new new grad on the bottom of the seniority list. That being said I'm not sure how it works where you are.

You need to speak up ASAP. Tell HR. Tell your manager. Tell your scheduler.