Performed 2 natural gas furnace maintenances. Did not replace upstairs 16x25x5 media filter, still in good condition and it will need to be replaced was remodeling is done. Replaced customer provided Aprilaire model 2400 media air filter. Cleaned and checked all components, checked blower operation, inspected burners and heat exchangers. Both systems operating properly. Upstairs has 2 ducts that will need to be reconnected. Will be making estimate with material list.