Thanks LostCause I have to check into that. The vinager did not remove the junk. I'll try some CLR or something in the next couple of days.
Usage is impossible to tell. We have done a complete makeover with CFL and insulations and a power monitor for the house. Our bills have been the lowest ever and every month I keep expecting it to jump. With summer officially here this would have been the real test. I'll see if I can find some kind of filter to add to the filter
. The theory behind it makes since so I think it would work but I really don't have a base line now so it would be pretty hard to tell.