Hi, basic water on basement floor. Water is sweating/seaping from the bottom of the central air unit. The unit is mounted for vertical blow threw. Drain has been checked and cleared. The unit has a lot of condensation. Drain pan is along the circumference of the heat exchangers, allowing condensation that drops from the center to fall to the bottom. What ever does drain down to the side of the heat exchanger does go to the drain pan. When I removed the filter, it was wet.
The g/f has explained to me that the thermostat control, which is digital, is showing two fans blowing, indicating that the unit is working extra hard. The unit is two years old. Last year, the unit had very little condensation, however the line did frost up. Repair man indicated that the ac duct was left open at the end of the run, cooling the basement first and causing the unit to work overtime causing the frosting of the lines. That was fixed. Performed fine rest of year. This year has just started and now having issues. Any and all help would be appreciated.Thanks in advance.

Strange. Check for restrictions on the return air. A new piece of furniture in front of an air return, etc. With the second fan on, the pressure could be low enough to suck air in the drain keeping the water from running out. Then, when the unit shuts off, all the collected water goes everywhere. In some cases, they put a trap on the drain, but I don't understand how they work.