So I’m having an issue with my geothermal loops. I did a 4 ton slinky loop system, 4 loops 600’ long each, and a non pressurized 2 pump flow center. Initial startup of the unit proved good. I was getting 12 GPM of flow, and 3-4° of delta-T. I had good heat and everything worked fine for about a week and a half. I came back one day to find that the geothermal unit had a low pressure lockout. I proceeded to check everything. The pump was moving water, refrigerant pressure was good. So I started it up again. It ran for several hours and then cut out again. This time upon further investigation, I found that the loop pumps had stopped moving water. The pumps were still turning but no water was moving. This was causing the low pressure lockout. I disconnected the pumps from the unit and ran them separately. The pumps almost immediately picked right back up and started moving water again. (Just FYI it’s a 15% glycol mix) water temps were running consistently 34° in and 31° out, a little cold but I had backfilled part of my trench on a cold day and the ground is still settling. The important note is that it hasn’t fallen to the glycol freezing temps. I’ve tried restarting the unit 2 other times with the same result. I am stumped as to why the pumps keep doing this. Any thoughts?