Your geo is so cheap that it is probably worth it even at your crazy cheap electric rates. I don't really know the climate in OK but in central NC, at your rates, you are looking at $500 a year for conventional ASHP and $350 a year for geothermal, so your payback is close to 30 years. That is assuming you use enough electricity from other things to get to the lower rates for most of your heat. And it is assuming that the house is built fairly tight. Your insulation levels make me think OK has a fairly mild winter. Geo makes more sense as your winter temps decrease and then it also tends to last a lot longer so your payback becomes the lifespan on a heat pump. And since you were quoted Goodman, that might be less than 10 years. Geo will also make more sense as your electric costs rise to more normal levels. At some point, electricity won't be 5 cents a KWH. Your math changes dramatically when it is 10 cents. Given the inability to get any money safely on investments and the low borrowing costs, it make financial sense to prepare long term for inflation. So even a 30 year payback makes a lot of sense since that doesn't factor inflation -- if this is your home you plan on living in for a long time. Heck - I plan on getting PV - it is basically a 5% ROI but that is great right now and it is a hedge against inflation

You didn't say if this was a heat pump system or gas. I'm going to assume single stage gas. try connecting C to C, that is, blue to C. Try connecting White to W1. Be sure to set up the new thermostat for single stage gas operation and not heat pump.

OK option 2 is the choice here but now I am finding it difficult to find the right parts locally. Accordling to the mfg installation instructions it says: "Where possible a good quality ground fault interruption (GFI) breaker is strongly recommended at the main power supply for all single phase electrical equipment in the pool system." The manual also explicitly states "Although Heat Siphons heat exchanger is electrically isolated from the rest of the unit, it simply prevents the flow of electricity to or from the pool water." I need a 30 amp GFI 2 pole breaker to meet the recommended installation. Problem is I cannot find one for a Siemens main panel. Do I need the GFI protection? Or is that extra safe? Its physically impossible to be in the pool and touching the heat pump unless I was 30 ft tall.

Thanks, Mike & Tigerdunes: I've been a builder for over 30 years so I tend to pay very close attention to the little things happening in my home as I'm the guy who probably installed it and has to fix it if it breaks. I had a Honeywell Wifi thermostat that was terribly unreliable in terms of its Wifi connectivity and lack of today's available features. I did not want one of the new Internet based DIY thermostats like Ecobee or Nest because they get their temp from the Internet, a temp that is always several degrees differant from my home. I wanted a hardwired outdoor sensor. So, I installed one and a Venstar T7850 Wifi thermostat that appears to be rock solid, versatile, easy to program and the connectivity is flawless. My brother is a commercial builder and uses them exclusively in his buildings with great success. It provided all sorts of usage data on a minute by minute basis if desired. It even has an installation test mode that checks your wiring and turns different components on and off to confirm your setup, which I think is brilliant. That said, I feel good about my wiring and setup. I can run 'Emergency Heat' with my inverter/generator during a power-loss, and everything else seems to work fine. My changeover point is set to 33 degrees which is determined by the hardwired 10 ohm outdoor sensor as it should be. My only concern is the one I mentioned in my initial post: I call for 5 degrees of heat, the heat pump comes on for a couple of minutes, then the furnace lights up due to the 5 degree call, and my heat pump does not shut down (or it doesn't seem to). It might be that it would shut down in a matter of minutes or might just be winding down in some cool-off mode. As I said, I am afraid to let it run just to see what happens because something bad might happen... like creating an over pressure situation and blowing a refrigerant line. I wish I could find out if this is not out of the ordinary for a heat pump but thus far nobody can tell me definitively as there are different variables, which is understandable. It's just hard to get anyone out here during this virus and the drive-time alone adds 100's of dollars before anything is even gets looked at. Sorry this got so long winded.