These EZAir units are made to last for a long time running 7 days a week 24 hours a day. You should not have much trouble but if you do its covered, you just pay the shipping charge and in the case of the EZAir units installed in the AC there is a slight charge for removal and reinstallation.
When buying the EZAir #5 for $860.00, its the most powerful unit of the plug ins,it makes since that you have powerful unit to kill mold and mildue etc., but also turn it down for small areas. The #5 would cover a house 2500 sqft. any smaller would only cover a room.