Found geothermal unit for second floor locked out on compressor failure to start code, checked capacitor and incoming voltage. Both are good. Reset code and perform test run from thermostat. System came on as it should. During rest run, check all electrical parameters to make sure that was no issues. Suspect that when power was lost to the house, and then came back on, the furnace control was glitched and went into a lockout code. No issues found or suspected with unit at this time.