Never been to Pennsylvania myself but this kind of place is right up my street. Old sanitariums are fascinating from a historical standpoint alone, before you even get into the paranormal side of things.
What's the layout like inside? Multi-storey or mostly ground level? I always find the layout matters a lot when you're trying to document anomalies properly - harder to rule out sound travel and structural interference in buildings with lots of floors and corridors.
Anyone done baseline EMF readings there or is it more of a casual explore situation? I've done a few abandoned sites on Dartmoor and the difference between going in with proper kit versus just wandering round with a torch is massive in terms of what you actually come away with.
Would love to hear from people who've actually been. Any documentation, photos, audio recordings - post them up if you've got them.