Upon arrival for double system tune up systems were on in cooling and both thermostats were satisfied at 78/79 I asked homeowner for filters to replace, he provided one for each system I dropped temperature on both systems and went into attic to begin tune up I started with downstairs system and checked deltas, downstairs had a 20 degree delta I then checked blower motor, blower wheel was clean and in good condition I then checked evaporator coil and it was also clean and in good condition Lastly I poured bleach down the drain line and chased it with 1 gallon of water with no backups I switched to upstairs system and checked deltas Temperature delta is 20 aswell but started climbing because of return being right next to attic access I then checked blower motor which was spotless and in good condition I then checked evaporator coil which was also clean and in good condition Lastly I tested drain line with bleach then chased with another gallon of water since both primaries were in li