Just had a new Carrier Infinity 38YDB/FE4AN HP installed. I have always been concerned about use of auxilary heat associated with high electric bills. I controlled it manually on my old system by minimal setbacks and only small step increases in temp after vacation preventing the aux heat light from comming on. The installer of the infinity said aux heat would not come on with programmed setbacks because the smart mode (on) gradually increases demand temp. However, aux heat is on every morning after a 4° nighttime setback (relatively mild California weather). I reset the electric heat to never come on above 40°F. This works but do I have a problem or was the installer wrong? The heat mode light pulses once about every 3 sec. in normal mode while the book says it should cycle 2.5 times per sec.