I found one of the AC110's empty the last time I cleaned sponges. I have no idea why but it was running dry. I have no idea how long. I emailed Fosters explaining the situation. While I was trying to get it running again, within an hour, they had already replied. I got the filter running again while I was awaiting their response. I simply asked them if they would help me in getting a replacement motor. Their response was to ship me out a replacement immediately and they asked for the return of the defective filter. It has since failed again and I will be returning it, but I got the new filter and everything is great. I didn't even give them my address or anything, they looked it up and sent it out before I even had the chance to tell them that I had gotten it working again. This kind of customer service is exceptional. I'm returning the defective unit at their expense, they even included a shipping label. Great job, Fosters and Smith. This was the first AC filter that had ever failed on me, and they took care of it faster than I could have asked for.