Thanks! CAD, the leaking condensate is not from the drain, but the slanted coil thingamajig right behind the filter, that thing with the thin fins and pipes where the air sucks up into plenum, then ducts.
100%, all, EVERY, refrigerant based A/C unit condenses water on that coil.
Actually, the "cooling" effect of air conditioning is mostly based on humidity removal, not cooling the air.
So, your unit is designed to capture the water, somehow.
We need a better answer from an A/C guru, but, possibly your fan is operating at too high of a speed, throwing the water where it should not be.
BUT, 99% of the time, it is just dust accumulated, causing the water to not get to the drain.
If it worked OK when installed, but, not now, something changed.
A savings of only $80 per month would hardly pay for the install over its life.
I would fix/keep what I got,,,,
My central heat pump was installed in 1979,, and is keeping me and my wallet happy!!
Here is an article I wrote on what I did to, among other things, keep dirt out of the A/C coil;
Cut the energy usage of your forced air cooling (or heating) system ? SweetMK