My wife and I live in a 2600sf ranch with 1300sf finished basement. Our house is very comfortable except for the indoor air. It feels cold and damp in the summer. The Lennox furnace /HVAC is about 3 years old. In the summer time the basement is so cold that we find it's uncomfortable to spend time watching TV down there. The humidity in the house runs from 50 to 65 percent Rh. The thermostat is on the main floor and controls the main floor temperature pretty well. I think I need to lower the humidity and I'm thinking of installing a whole house dehumidifier on the furnace. . Any suggestions?