The unit should be inspected once a year by a qualified service technician.
Units are equipped with four 20 X 25 X 2” filters. Filters should be checked and replaced when necessary with filters of like kind and size. Take note of air flow direction marking on filter frame when reinstalling filters. See figure 20. Filters must be U.L.C. certified or equivalent for use in Canada.
Clean condenser coil annually with detergent or commercial coil cleaner and inspect monthly during the cooling season.
Condenser coils are made of one, two and three formed slabs. Dirt and debris may become trapped between the slabs. To clean between slabs, carefully separate coil slabs and wash them thoroughly. See figure 21. Flush coils with water following cleaning. NOTE - Remove all screws and gaskets prior to cleaning procedure and replace upon completion.
H-Supply Blower Wheel
Annually inspect supply air blower wheel for accumulated dirt or dust. Turn off power before attempting to remove access panel or to clean blower wheel.
Source: MaintainX (Community Member)