I talked with Terra Source today. I got to talk to the guy that designs the loops very helpful.
One pipe option is SDR-9 pipe 3/4" size is pre-charged with 190 proof industrial antifreeze.
This system is pressurized but flushing is simpler since loops are pre-charged with antifreeze and sealed.
I would need to buy a larger bucket a 16” bucket for my backhoe (that is the biggest bucket I can run). I would have 4 loops but put two loops per trench.
Two 300’ trenches each having two loops. This would cut my install time by a lot.
3-ton Tranquility 30 system with some extra loop pipe and keep the mini splits.
Warranty is done through them. DIY does not void warranty.
I put the numbers through the software and it looks good to me.
The installer that did my quote said the don’t use aux heater coils here.
It is $236 to add 10K auxiliary heat coils. My mini splits only work down to 5 degrees.
In the last 5 years we had one week where 4 days it was colder that cold. I still wonder if I should install them.
Cost is $9,560.56 depending on shipping could very a little.
My out of pocket cost would be $4,302.25 after tax credits.