Troubleshoot: New Furnace Putting Net Current onto Six Different Circuits

[UrbanFarmer]

Hey Everyone:

Can someone help me troubleshoot:

I have been going through my house across the past several months correcting wiring issues. I live in an old house, built in the 50s and whoever did the electrical work... all I can say is that they did their best and made the lights come on but it's a mess. There are shunted (shared) neutrals between different circuits and improperly wired 3-way switches and on and on.

Here is my question: I was working at the panel testing for net current at each separate breaker. I discovered that when I turn the breaker for the furnace ON that net current flows on five individual breakers--even if those breakers are off! When I shut the breaker for the furnace off, the net current disappears, again whether or not the particular breaker that had the net current is on or off.

Has anyone seen this before?
Can someone tell me where the bleed is happening?
I don't see a jbox where the powerline from the panel to the furnace is crossing any other circuits... but it is possible that the box could be buried because electrical code and practices were different back then.
Is it possible that something is going on in the panel?


Any and all thoughts and ideas appreciated.
Cheers!