When we first started having trouble, I asked the office if I was supposed to change the filter or if they were (I reliazed that in the four or so months since we had lived there, I had not once remembered seeing maintenance change the filter in the unit in the attic). They told me that maintenance changed the filters and that I was not to. One thing I did do, however, is I took off the covers to the two intake vents (one downstairs and one upstairs). I could tell this had not been done in a while as there was a lot of paint over the screws of the vent covers. What I found was a tremendous amount of dust/dirt. I vacuumed all of this out. When I mentioned this to the A/C repairman, he jokingly said I probably vacuumed out about 30 years of dust. This is something I routinely would do at the house we previously lived in. Is vacuuming out the intake vents not considered normal maintenance that the apartment is responsible for? I was hestitant to do this myself at first because I did not want to do anything that the apartment complex could later cite against me. Speaking of humidity, I bought an inexpensive digital thememoter that also reads the humidity level. Before the unit was replaced, the humidity would stay around 51 - 55%. After they replaced the outside unit but had not yet replaced the evaporator coil, the humidity got up to 63% or so. Since they have replaced the evaporator coil, it has been reading around 51 - 52%. Is there a limit to what the inside temp can get where the apartment is supposed to legally do something about it? If the temp gets 80+ degrees with the A/C running, is this considered acceptable?

If you turn off the first floor AC, does the lilac smell migrate to the first floor from your cellar table? If not, you are right and the installer is wrong. You have a duct leak somewhere that is drawing cellar air into your system. That depressurizes the cellar and pressurizes the first floor. Outside air is then sucked into the cellar and inside air blown out of the first floor area. That seems like way too much air leakage for a new system. It is inefficient at best, but it can cause other problems as well. Depressurizing an area of the home can be dangerous. It can prevent the exit of combustion fumes from water heaters, boilers and furnaces and fill the house with them. What kind of heat and water heater do you have and where are they located? If you cellar is cool and outside is humid, drawing in outside air could lead to higher humidity in the cellar if the dew point of the outside air is lower than cellar temperature. f the system is not supposed to condition the cellar, you should not see much of an effect on humidity down there. What was the cellar humidity like before AC install? You might have to attack this problem separately. Is it warm or cool down there? Did the same outfit install the second system?

christine1950- I'm including a link for applying bubble wrap to your windows for additional insulation in the winter, using nothing more than water from a spritz bottle, so it's easy to do and completely reversible. We've been using this tip during the winter for a number of years and getting great results. Our home is 7-years old and has energy efficient windows and we can still tell a difference - especially the bay window in the dining room when we sit down to eat. Tips about using this method.... -Cut your bubble wrap just slightly smaller than your window. If the bubble wrap is a little too generous and is larger than the glass, it will quickly get air under it and begin to pull away from the window. -Check your bubble wrap occasionally and spritz it with water again if it's pulling away from the window. -If you have hard water, use distilled water for the application. Hard water contains minerals that can actually etch your windows. -Bubble wrap with large bubbles works the best, but we have plenty of windows that have bubble wrap with small bubbles on it. -Check furniture stores for a free or cheap source for bubble wrap. -Grainlady Here is a link that might be useful: Bubble wrap window insulation

To answer what we did before AC, we chose the drier/cooler Fall to paint outside and inside we waited until the winter. I googled: The ideal humidity level for painting is between 40% and 50%. If you're indoors, it's easy to attain that level with a dehumidifier. When you're outside, though, it's not as easy. If necessary, you can paint in up to 80% to 85% humidity.