Luke,

I saw the same thing in a house 10 years ago. It had a floating
ground. We were putting in a new heat pump and got lit up when we cut
the Freon lines. This is really dangerous. It can kill you or damage
all your electronics or BOTH. Unless you know a lot about electricity,
have the test equipmentm and know how to use it - DO NOT MESS WITH IT.
This not the job to learn on!! Call a licensed electrician, this is
not a good place to save money by doing it yourself!!

Stretch