An often forgotten part of routine RV maintenance is the roof A/C unit. The unit should be cleaned and checked at least once a year. A good time to do this maintenance is early in the season to ensure that the A/C unit is in top operational condition for those hot summer days.
Remove the A/C cover and use a wire brush to gently clean the evaporator coil fins. It looks like a small radiator. The brush will remove dust and dirt trapped between the cooling fins and around the coil. Using compressed air, blow the dust from the inside of the unit to the rear, working up and down the evaporator.
Check the motor to see if it has an oil fill port to lubricate the fan shaft bearing. Some units are permanently sealed and will not have the tube to add oil. Put a few drops of oil down the tube and replace the cap. This will help keep the bearings properly lubricated and will avoid potential problems with the motor seizing or the bearing to fail.
Check the cover for needed repairs due to cracks or damage around the attachment holes. Repair as necessary. Most covers can be easily repaired if they are caught before the cover is too badly damaged. Replacement covers can be purchased but they are not cheap.