Came out to call to perform preventative maintenance on heat pump system. Discussed with customer about maintenance being provided, filters, and any issues. Customer had already replace the filters in home and said system has been working well. I started my inspection of the air handler in the attic. Inspected all electrical wiring and connections, heating elements blower assembly, motor, evaporator coil and ductwork. Cycled emergency heat and checked temperatures, pressures, and amps on all elements. Inspected heat pump coil, electrical components, and wiring. Cycled heat pump and checked amps, temperatures and pressures. Tested defrost controls and reversing valve. System is heating properly at this time.