I have a older model heil outside unit, and never have had it running, the problem is when you turn the therm to electric heat it runs fine, but when you switch it over to normal heat , the lights in the house go dim for a second, not all the way dim, sorta like something is jerking too much electricty and when I switch it back to emerg. heat is works fine, the heat pump is wired with 6awg (50amp breaker)60 in the house) and 10-3 with a 35 amp breaker( 45 in house),which is the one that caused the lights to dim?? is the compressor bad??
It sounds like your compressor is having some start up issues. I would reccomend having someone come and check your run and if it has them the start capacitors. You could have a bad run capacitor causing a phasing problem. Or the start capacitor is out of range. If that be so they will need to install a new potential relay along with the start capacitor. If yours does not have a start system on it and the run capacitor is ok, you can install a hard start kit and eleviate some of the problem but that is just putting a bandaid on a bigger problem. If you end up installing a hard start kit, you will eventually loose the the compressor. At this point if the heat pump is older than 10 years, do yourself a favor and replace it. Hope this helps.