[Gippetto]

I don't believe the polarity is reversed cause the welder has been fine since I bought it three years ago and the problem just started.
I just heard back from Miller's tech guy and he concurred that it might be a connection issue where the gun plugs into the welder. He said if there is no short in the wire spool and if the gun connection is good to replace the entire gun assembly.
Sounds too drastic. I am getting back to him depending on what I come up with when I check the connections.

Thanks for the suggestions.