Heat Pumps and Electric Heating - Heat pump operation

Armstrong Air heat pump Concept 1000, 2 ton, 2-heat strips(5kw each). Tstat Robertshaw 9620. I thought proper operation meant when the heat pump falls behind say 3 deg, the aux kicks in-which means condenser remains running and 1 heat strip turns on. If this is still not enough then it would be up to me to manually switch tstat to Emer heat- which would then turn off the condenser and activate both heat strips. I believe this is a 2 stage heat pump. The sequencer is a double stack. I have seen multiple times when the aux light is on, the condenser is on & both heat strips on. This does not seem correct, if not what is causing problem? BTW my kwh usage has more than doubled from last year at this time.

Armstrong Air heat pump Concept 1000, 2 ton, 2-heat strips(5kw each). Tstat Robertshaw 9620. I thought proper operation meant when the heat pump falls behind say 3 deg, the aux kicks in-which means condenser remains running and 1 heat strip turns on. If this is still not enough then it would be up to me to manually switch tstat to Emer heat- which would then turn off the condenser and activate both heat strips. I believe this is a 2 stage heat pump. The sequencer is a double stack. I have seen multiple times when the aux light is on, the condenser is on & both heat strips on. This does not seem correct, if not what is causing problem? BTW my kwh usage has more than doubled from last year at this time.

Any chance you hit the reset button and the stat went back to factory settings? If so you would have to customize your stat again with a higher temp differential.

No, everything is still set the right way. I have a separate meter connected to only the air handler conductors. It keeps a cumulative total of kwh used per day. The air handler alone is using from 40-80 kwh per day. Last year our highest month we averaged 54 kwh per day for the entire house.