Anyways, the only other thing that comes to mind is as follows. All of this was done sometime back. Most probably at that time it was heating only HVAC (no cooling). The proof in the pudding is many of my neighbors still have the oil-based HVAC (huge tank in basement) and no centralized AC, just window ACs. Is there a possibility that these manual J, D, S, etc. are different for heating and cooling ?