I had an Intertherm 10 seer unit 2 ton unit and just had a Ducane 13 seer 2.5 ton condensor and evaporator coil installed. The problem is only a 12-15 degree difference between the out and inside air. Also the coils sweat properly but don't run at a diagonal down like they are supposed to but drip directly down outside of the drain pan so I have had to shut it off. I had also complained right after the install that the air flow is only about 1/2 of what it used to be. The tech says it is charged and installed properly and I must have a duct work problem causing it to pull in too much outside moisture or maybe the fan motor is acting up and needs replacing. He won't go ahead and replace the fan motor until I have the duct work checked.
One thing I did notice besides the air flow is 1/2 of what it was is that the new coil says it is and upflow/counterflow and my unit/cabinet was and is set up for downflow. Is this a problem?