why a ground wire on a/c condenser unit?

Read following article on Electrical Grounding .

Nothing jumps out at me. Is this the same 220 circuit? I would first unhook the line from the load in the bathroom heater. Check the voltage. At some point, unhook the connection in the laundry room and check voltages in the bath. Let me know what things look like. Oh. One way this could happen ...

Yes you do . the two grounds go together as do the two whites and blacks. you have to pigtale off each wire to wire to outlet.

Give as much information as you can. Describe the layers of the flooring starting from the beams that hold up the floor and work your way up. Do you have access underneath the floor? What is causing the condensation? Has the problem been fixed?

Hi Rich, the tank needs to be grounded, but should be from having been bolted back in. The sending unit gasket 'may' prevent grounding, but most senders have a ground attached to their case. That should be grounded to the frame as well. Like I posted in the oil pressure thread, the gauge reads ...

As the property owner, you must remove the offending tree or the power utility will do so for you -- at your expense.