The loop temps will drop for sure as winter goes on. Don't know how low though. It dropped into the low 20's last winter but only half of the loop was complete.
Looks like it runs 2.75kw with the second stage on. Air out temps have hit 104F on second stage.

When the loop temp dropped into the low 20 does second stage run more?
How many SQ feet are you heating?
Thanks for all the info.

I'm trying to remember correctly now, I don't think the loop input temps hit the low 20's but for was in the 20's. Out temps were low 20's, maybe even down to 18 and was getting concerned. At some point the pump faulted out as it started to freeze the liquid. Nice fail safe features on these things. Added another 5 gallon of antifreeze and it didn't happen again. In any case, the second stage was disabled last winter because there just wasn't enough loop to support it. I hope to stay in a more efficient range as far as loop temps go this winter.
2700 sq ft.

Thanks for all the info. I am putting in a horizontal loop in next few weeks. 3 ton 2 stage we have 2100 sqft.
The ground temp here starts out 60 at least that is what another person with geothermal that lives close to me told me. The numbers you told me helps me even know are systems different it is still useful info.

Do you think your system does better heating of cooling?

Not that i'm a pro or anything on the subject, but as I understand it, in most all cases a heat pump is more efficient at cooling than with heating.

This has been an amazing DIY project and to now see it payoff with very reasonable priced heating and cooling is the cherry on the top.
It must pretty sweet to see all your hard work pay off.