A:Answer I haven't tried it with this unit but with my previous unit I opened up the panel and cleaned it out thoroughly, which had a significant impact on its cooling ability. I first cleared off large chunks of accumulated dust (which had turned into batting, since I'd owned it for years before opening it up), then vacuumed, then used a paint brush to clear out the rest of the dust. Then I used a toothbrush and vinegar to clean the coils and let it air dry for a long time. It smelled like vinegar for about the first 15 minutes of running it but was fine after that. Ideally if there's a service manual available for the unit you could look into the proper approach or check the FixYa site, but I couldn't find one for mine and risked it anyway.
What most units recommend at the end of the season prior to storing is to drain all water thoroughly, then run the fan for a few hours to dry it out. If you want an easier project than the above, that's what I'd recommend. Although when I opened mine up I realized water, rust, and light mold had accumulated on the inside in some areas that wouldn't have been reached by the fan approach.