We just replaced our air handler about a month ago, and it already seems to be breaking down. When we set the thermostat to "Cool" and turn it on Auto/Fan Only, it comes through, but very slowly.

We thought that this might mean the coils were frozen, so we switched the cool/off/heat switch to off and turned the fan on. Nothing is coming out.

We live in Maryland, so it's super humid, but even last night when it dropped down to 75 degrees our house never dropped below 80? I'm not sure what the problem is, is it possible that the air handler's fan is broken, so the light air that comes through when the A/C is on is just because of the outdoor unit's fan?

Again, the air handler is new, so we know it's not the filters. We're having our air ducts cleaned today, but since nothing was coming out with the fan only option, I'm guessing that's not it. The outdoor unit is older, but it's running and the tube running from it is well insulated, though I can still feel the cold condensation coming through the insulation.

We just spent a ton of money getting the air handler installed, so I'd like to avoid calling a technician in again... Any ideas?

Thanks!