David, Good point, perhaps this is what KY Ted is trying to do. Do you check the temperature rise? If so, would that not give you sufficient information for a home inspection?. You know, tizz working, or taint working. George Sure. And that's the basics. But I find it easy enough to go this bit further and describe the situation where I only get 20 amps draw, and the breaker is a 60 amp. I don't know what's wrong, but that's enough to say that either one's there and not coming on, or the breaker is oversized. The real limitation of this method comes with newer heat pump auxiliaries - which sometimes have a limit switch that only allows one element to come on if the ambient temp is moderate. If I suspect that, then I just waffle: heater came one, or didn't come on. -David Lee