Heat performance tune up times one system. In fact blower, evaporator and ductwork. Test all safety features. Tightened on wire connection. Located two broken spades on the heat strip relay. Repair those and they are operating properly now. Test if he tries. 40 degrees temperature rise. Check outdoor unit. Refrigerant level good at this time. Test capacitor ,contactor and defrost cycle. Wash condenser coil. System operating at manufacturer specs at this time.