I'll have to think it through, it was many years ago. I was working on the roof where the ac unit was not working . As I remember the feeders came through the roof into a j box where 1 phase- 2 conductors. Were sliced by split bolt with 2 more conductors and one conductor went to ac and one to heat unit. The same was done with the other phase. I could be wrong but I remember hearing the heat and the ac aren't on at the same time so it can work.
The #8's were spliced by a split bolt & then served the AC portion & the heat portion separately. I say this is not a parallel conductor situation. Just one branch circuit going to separate but related loads in your equipment.
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The oven landed in a 4-11 behind the oven 2 blacks,2 red's. Connected to the oven whip.
