Refinance vs line of credit?

[Winga Blaggard]

I have a property with about 4% interest rate, purchased with 20% down a couple years ago.

I'm considering refinancing it - hopefully can get a better deal.

I also am hoping to use the equity in it for a downpayment on another home this summer. 

What is the best course of action to achieve this? Would one preclude the other (i.e. would refinance get in the way of taking an equity line of credit)?