Found system off upon arrival - turned system on to cycle - system started up in defrost cycle. Believe problem encountered was defrost operation - allowed defrost mode to finish and checked cycle of heat pump and electric heat. Everything runs normally at this time. Explained the defrost circuit and normal operation of heat pump. System will check after about 90 minutes of run time if there is ice on outdoor coil and will shift into defrost. Part of the defrost operation is to stop the top fan on the outdoor unit, shift the unit into cooling to raise the temperatures and pressures of the refrigerant to help shed off the ice. The normal byproduct of defrost will be water dripping from the outside unit and sometimes steam coming from the top of the unit.