IMHO we aren't getting very far until we have evaporators in each zone. At this point nobody is willing to spend what it takes to make home systems truly efficent.
What good is efficiency if the gains are only incremental. Plus in the us, most of the population lives in either a mild climate (west coast) or a climate that's heating dominant and for the most part natural gas dominates.
I think you have to take an evolutionary approach and let comfort drive demand for high end equipment and allow energy prices to dictate to a certain extent what SEER equipment consumers will purchase.
Anyone one installing servicing the variable speed condensing units? Nordyne, Carrier, Trane etc.. I want to get some feedback from folks who have had hands on to know the bad, good or jus plain ugly.....
I have not done one in a couple of years(IQ drive).it is a great technology.The tsat is the heart of the system controlling the compressor and fan speeds.It also had electronic txv units.The claim was it could go 118% of its rating.We took out a 5 ton and put in a 4 ton.It ran well and customer said when I went back to pm it that it kept up in the summer.Better than his original.