I have 2 LG Dehumidifiers (3850A20500H) running in my 1500 sqft unfinished basement. The past two years they have worked great and have kept our collectables at a comfortable RH (set at 50%). However, when I went to turn them this spring/summer, they are not condensing moisture as in the past (from filling basin daily to less than a gallon/week). I don’t have the owner’s manuals anymore; any thought about what is going on and/or is there any kind of maintenance that I can perform on them?