AC Condensation

I have a Trane 5 seer that's about 3 years old. Recently heavy condensation started. The inside unit is where it all starts and it leaks down to some pvc pipe that routes to the outside of the house. The filter is wet and the whole area around it is wet. It's not leaking beyond the inside unit, only to the outside of the house. When we first bought the house the builder said we should pour about a half cup of bleach down a drain hole monthly or if it starts to drip outside during heavy use to stop some type of build-up, (I forget exactly what) but we've done that. I opened it up and cleaned it out as well as I could, I just found dust accumulation. It cools the house very well and I talked to a couple of people who work in the a/c business and was told this was normal due to the high humidity and heat here, (I live in San Antonio, TX). I've never seen this much condensation before and I wonder if it could be a major problem and should I call a repairman in or should I just not worry about it.