heat pump and air handler systems are expensive in the winter regardless of hspf (efficiency) rating. below 40 degrees your going to get most of your heat from the auxiliary electric heating elements in the air handler. (basically a larger version of the heating element in a toaster) anything that glows red hot and uses electricity will draw a lot of amperage. I have 15 years of residential experience a md state masters license and offer competitive pricing . Message me if you would like an estimate