Upon arrival customer explained that upstairs system would not maintain set point. Performed thorough evaluation of entire system. Found air filters very dirty and in need of immediate replacement. System only producing 13° temp split. System charge low on R22. A leak search must be performed in order for system to be charged. Found evaporator coil very rusty and impacted requiring cleaning. Blower wheel impacted and needs chemical cleaning. Blower capacitor failing and needs replacement. Condenser coil impacted and needs chemical cleaning. Compressor capacitor failing and needs replacement. System is 21 years old and has passed its life expectancy making it more prone to failures. System replacement is recommended due to age, condition and estimated costs of repairs. Customer will call us tomorrow once Mr. and Mrs. have figured out a time to speak with a comfort specialist. Recommend joining Comfort Advantage Club.