For all the reasons known to people on this forum, we installed a geothermal heat pump when we built our house outside Portland Oregon (USDA zone 8); we have had nothing but trouble with it! First the contractor ran it for construction heat (radiant floors) and ---according to him--it froze the ground and became useless until the next Spring. We had to install an electric heater to survive the winter/Spring. Now it kicks off and needs re-setting all the time. It cooled the house this summer reasonably adequately. It is now winter and it is struggling to heat our 3000 sq. ft house. It was very expensive to install. Has anyone else had these problems?