Do the typical differentials for split system A/C units also apply to geo-HVAC units? Is excessive condensation on attic unit and on supply registers common for geo-HVAC?
What is ever acceptable about excess condensation?
Write up what you see and express your concern. Move on.
Moisture in the wrong place is ALWAYS bad.
General operation of a geothermal system is exactly the same as a more common split system. The only difference is that it is a single unit and the freon is cooled (or heated in the winter) with a heat exchanger instead of pulling air through the coils on the condensing unit.