If you got a CCW license, then it's not issued by the state of Pennsylvania
It's a License to Carry Firearms, and makes no distinction between open and concealed carry. If you have a LTCF, you can carry anywhere in the state, open or concealed, except past the secure areas of courthouses and on Federal property. In some other areas, like casinos and state parks, carrying a firearm is a ticketable offense. But essentially, with your LTCF, you can carry openly wherever you can carry concealed.
Even if you didn't have a LTCF, you could openly carry under certain circumstances. A LTCF gives you the flexibility to carry concealed, open, or anywhere in between, and allows you to carry in cars, in Philadelphia, and within 1000 feet of K-12 school property (Federal law).
Also, "no guns" signs posted at businesses do not hold legal weight in Pennsylvania. But if you are asked to leave, whether because you're carrying a gun or for some other reason, and you refuse, you can be cited for trespass.
More information and citations at http://www.paopencarry.org/