Somewhere, I'm not understanding either. We too have a three stage geothermal system. We have a closed loop of two 300 foot wells, which have an average temperature of 53 degrees. The loops enter the house just above the basement floor, so the closest they come to the ground surface is about seven feet. Outside temperature should not have any effect on when the compressor can run.
We have our system set so that we have to manually turn on the emergency heat.
With that said, our system has gotten "confused" a few times. It just happened two nights ago again. Nobody knows why, and the service tech is again coming out today. We have four zones, and when it has gotten confused, the emergency heat has come on, and the dampers to the parts of the house that are not calling for heat will open. Both times when it has happened, the thermostats in those areas were set to 62 degrees, and the areas had reached 72-74 degrees before I discovered the problem and reset the system.
One of my fears is that the control system is so complex, they may never figure out why this happens. My other fear is that this will happen sometime when we are away from home for several days.
If the tech comes up with any good answers today, I'll be sure to post.
