Newbie here and I have a doozy of a problem.
Here is the scenario : 1800 sq ft, condo in coastal SC. Only exposed walls are the front and back (about 700 sqft total), the top, bottom and sides are all adjacent condos with functional HVAC and normal temps. In the summer months, owner reports significant humidity problems and condensation on vents (bathroom, microwave and clothes dryer). I placed a data logger in the residence to find temps are maintained properly per thermidistat settings, but the humidity cannot be kept below 70%. No evidence of plumbing leaks, etc.
Ran a blower door to find exchange rates of about 5.
The existing HVAC system was a 3 ton system. We replaced the whole HVAC system with a 2 ton system. Humidity levels seemed to drop by about 5-10% on average, but still stay around 65%. We then sealed some known openings in the front and back walls to try to reduce the exchange rate (haven't retested with the blower door). Preliminary findings suggest tightening the construction did not result in humidity reduction.
Thoughts or suggestions?