@Sigarms. Yes, in my head those were the same. I don't think we will deal with geo. I appreciate your expertise. I love the variable speed on our AC and other than that, we will try to balance up-front cost and efficiency.
I assume you mean the blower motor in the gas furnace.
Keep in mind, you could ask for a variable speed AC, which would mean you would get the mac daddy variable speed compressor in the outdoor unit.
In the good old days, blower motors were simple. PSC (fixed speed), X-13 (multi tap which would allow lower air flow in cooling for better dehumidification, and variable speed that could adjust the airflow continuously and in generally always used with mutli stage compressor in the outdoor unit.
Reason why I mention this is manufacturers I find use decieving techniques by what they call their blower motors now. A lot of manufacturers call their indoor blowers "variable speed", when it's really a fixed speed constant torque motor (X-13).
Today's "new" terms...
Varible speed constant airflow ECM = ("True") Variable speed
Variable speed constant torque ECM = old X-13 (better deumid over fixed speed as it can reduce the CFM's by a certain percentage)
Fixed speeds constant torque ECM = the upgraded old single speed PSC motor that has been discontinued due to government regulations in gas furnaces only (oil furnaces can still use a PSC blower as well as air handlers).
I have absolutely no doubt that customers today think they may have a variable speed blower motor in their indoor blower (gas furnace or air handler) when they really have a "variable speed" constant torque motor because the contractor didn't explain the differences and just used the term "varible speed" blower.
If I were building, ensure you insulate well. Insulating the house to lower the load for cooling and heating is the best investment you can make in your home IMO. If using a GC and you don't have direct contact with some of the subs (such as HVAC and plumbing) be very speciffic on what you want. What ever you do, don't spend good money on a HVAC system and good ductwork only to have a $35 Dico thermostat put on the wall
I just can't believe some houses today with all the upgrades homeowners go with and money spent on to have the absolute cheapest made thermostat put up on the wall.