I have an additional question on this subject...
Living in south FL it's hotter than heck most of the summer. Our A/C is working fine this year (thanks to the helpful people here who insisted I had a leak in the return that was pulling attic air). While the A/C does a good job of keeping us comfortable it gets overwhelmed when we have guests over or when cooking a big meal in the early evening (when the natural heat load is worst).
Since a two ton works fine for most situations I was thinking of having it replaced with one of the new two speed units and sizing the lower of the two at two tons then we would have the additional capacity of the second speed to cope with the days when we need more cooling. Will this work OK or am I missing a big part of the picture?
Steve B.