I was looking for a little advice. I have a Lennox furnace and I added central air a few years ago. The house is older (ductwork etc). The furnace is probably 10-15 years old, but still works great. I got several bids on the AC and all rated the house needed 2 tons, but 2.5 to be safe. That is what they installed. It blows very good cold air, but just not enough of it. I did the tempature check, and it is over 30 degrees cooler coming out than going in. I am wondering if the cold air is heavier and the motor just doesn't push the air as well?? I set my thermostat at 78, and it runs pretty much all day and almost all night in 95 degree weather. It will bring it down to 80ish, but almost never below that. I guess I may have some duct leaks, although I don't think they are significant (is there a way to check for them?).