Sorry, but this newbies search didn't turn up a definitive answer and aridirectory.org's search is overwhelming.
I may be in the market for a two-stage AC compressor to meet the 15+ SEER bogey. I'm an old bachelor in a small house in NE Ohio who only misses central air for about 7 days in the typical summer. My current two-yr old Nordyne G6TC-092C-VBA furnace has a cased G3BA-036 coil, never hooked up. If there are no ~2.5 to 3 ton R22 AC compressors, please favor me with some more newb questions.
My current coil is a two row, 15 FPI coil with 4.18 ft**2 area and 0.21 pressure drop at nominal cfm. I notice Nordyne's R410A coils have about the same area, pressure drop, and fpi (14), but three rows and TXV. My G3-036 coil is rather oversized as calculations done prior to the furnace upgrade indicated a two or 2.5 ton AC would suffice. Could an uncased Nordyne R410A coil be slid into the current case to minimize my install and fab costs? Would it be really dumb or even work to have a #918125 TXV replace the orifice instead?
The install is going to have to wait until summer (electrical upgrade), but even if I opt for a more conventional R22 compressor, are there any downsides to sizing the suction line at the 7/8" diameter for R410A over the 3/4" R22 spec, besides the obvious material costs?
Does an upmarket brand with an increased warranty have any durability advantages over the same mfr's downmarket unit? I do appreciate and concur with the common sentiment that the install is very important, but I'd like to narrow estimate requests if possible.
Finally another lazy question: Will natural gas costs at say two times current rates and electrical at ~$0.25/kwh dictate whether I should consider a heat pump vs just AC? IE: short answer (I know there are many variables), does the incremental cost and reduced lifespan of the heat pump vs AC only make sense? My current electrical cost with no demand meter is ~$0.125/kwh.
Thanks for the tolerance,