Tech arrived at a 2 system home warranty tune-up. Upon inspection, the capacitors were within specs. The contactors were in working condition. The condenser coils were hosed off to assist with air flow across the coils. The Upstairs system was low on refrigerant and had a low Delta. The filters were replaced. There was no observed drain safeties. The ductwork and blower areas were dirty. The customer was informed of recommendations today. He would like a follow up on the filter upgrades next week. He will send the information to the warranty company. The system was functioning upon departure.