I am in the process of replacing both of my evaporators (separate units for unstairs/downstairs). I have had a number of AC companies give me their opinion on what I should do. Most of the companies want to match the size of the evaporator units with the condensors (i.e. 3 ton to 3 ton). One company wants to install a smaller evaporator coil (i.e. 3 ton condensor to 2.5 ton coil) Their claim is that this system will remove more humidity since the coil will get much colder (I live in Houston - a very humid climate). I can understand the logic of this. However, this company installs custom systems not off-the-shelf units so their systems are 2 - 3 times the cost of an off-the-shelf unit. Plus their warranty 3 - 5 years parts and labor isn't as good as some of the off-the-sheld units. My questions are: 1) Should I consider getting an off-shelf-model with an evaporator coil that is smaller than my condensor outside? My only concern doing it this way is the fan will be rated too small and I won't get enough airflow. 2) If I do go with an off-the-shelf unit, can I (or should I) go with a unit other than Carrier? Carrier comes with only a 3 -5 year parts and labor warranty. The American Standard that I have been considering comes with a 10 year parts and labor. In addition, the Carrier uses a metal primary pan whereas the American Standard has a plastic one. Since the main problem with the old units is that the primary pans have rusted out, I would think that going with a plastic primary pan would be better. Here are some facts about my home. As you can see, the evaporators are pretty old. Location: Houston, TX House: 2000 sq feet (1000 upstairs, 1000 downstairs) Condensors: 2.5 ton Carrier Heat Pump upstairs (1998) 3.0 ton Carrier Heat Pump downstairs (1995) Evaporators: 3.0 ton Carrier Upstairs (1988) 3.0 ton Carrier Downstairs (1988)

On one side of my basement, I have a 275 gallon fuel oil tank that feeds both my oil fired hot water heater and my oil burner on my furnace for my forced air heating system. The water heater and furnace are on the other side of the basement. The 3/8 flexible copper line spans the perimeter of the basewment along the intersection of the floor and wall and is approximately 43 feet in length. The basement floor is concrete and the walls are concrete block and both the floor and walls have been painted with a latex paint made for concrete. The basement is very dry. I am concerned because at various places along the way, the copper line has a thick build-up of aqua or blueish green corrosion all around it. My question is, is this corrosion actually eating into the copper line and will it eventually cause a leak, or is this corrosion simply some sort of reaction that will not cause detrimental effects to the line? Should the line be replaced or is this nothing to worry about? Is there something made especially for cleaning this corrosion off of the line? If I replace the line should I use compression fittings or flare the ends of the line and use flared fittings? If flaring is the way to go, will a single flare be adequate or is a double flare necessary? :confused: Thanks for any and all responses.