Performed CMA full service. Newer Trane Symbio gas pack (serial 112L) had numerous heating failure codes due to burners being overfired. Tech adjusted gas pressure to 10" high stage and 4.9" low stage per install manual. Gas pack (serial 494L) has 3 larger style inshot burners showing significant corrosion. Tech recommends replacing burners. Outdoor unit 8 (serial EU4F) has a failed 5uf outdoor fan capacitor reading 0uf. Replaced for testing purposes. Tech also found low delta t and slightly low refrigerant pressures. Leak searched system and found no obvious leaks. Tech recommends replacing fan capacitor and adding 1 lb of R410a. Split system EMGF in the back youth area is very low on refrigerant. Tech estimates 4-6 lbs low. System is under 2 years old. Tech leak searched system and found liquid line valve core leaking and brass cap loose. Tech tightened valve core, but it did not stop leaking. Found no other refrigerant leaks in system. Tech recommends replacing valve core and ch