Arrived to service call and performed non club tuneup to heater. Customer stated water coming from heater area. Found clogged drain when washer drains it is backfilling into furnace floor drain. Informed customer that plumber will be needed. Performed tune up to 25 year old air handler. Lots of rust on evaporator coil which could cause air conditioner problems in future. Test capacitor and motor amp draw it’s in range. Elements in range. All sequencers and limits in working order. Cycled unit multiple times to insure that all safeties are working and unit running as designed. System is heating at this time. Due to age and condition of unit i suggest replacement be considered in future. Gave ballpark replacement price. Suggest regular maintenance to keep system running as designed. Filters need replacement customer will replace filters. Customer has had some sand out floor vents in past. Due to floor vents being in concrete I suggest have ducts scoped to see condition of vent pipes be