I had a 1.5 ton condenser installed in my top floor (2nd story) 800 sq ft condo last year. The bryant furnace/evaporator are old (32 years old I think) but furnace works great during the winter and the contractor who put in the condenser thought the evaporator looked fine and recommended to not replace it. But now the ac runs and runs and cannot seem to lower the temperature...even on mild days. At best it lowers it 1 degree and hour if I'm not in the condo but if I'm in the condo it sometimes goes up or never changes. It removes humidity just fine. I looked at the freon pipes going to the evaporator and the one going in is very cold but the one going out to the condenser is not hot like other units I've seen...it's about room temperature or maybe slightly lukewarm. Shouldn't this be hot or at least very warm? The contractor insists the old evaporator/furnace combo are fine and doesn't want to replace them but he's come out 4 times to recharge the freon or play with the air flow patterns but it never gets better. The temperature shift from intake to exhaust is like 15-17+ degrees colder to the exhaust, he thought that was fine. The lady downstairs has no ac and my floors are wood and possibly poorly insulated because I can smell it when she lights a cigarette...I wonder if that's part of the problem. I've tried to insulate everything I can... Any ideas?

What is the most efficient thermostat setting for making the best use of a heat pump in the cooling mode and in the heating mode and save money with my energy bill? I cannot find this information anywhere. Can anyone help on this.