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Question

I have a Kenmore Electric Air Cleaner Modle # 85264 the other # that is on the back is B1100341 I have tried the service center for Sears and was put on hold for over 40 min and still noone came back to help. So here goes this Air Cleaner will run for about 30 to 40 min it makes a electrical buzzing noise than it shuts its self off. On the frount it blinks clean cell now and the button blinks as well that says check cell I can not find any info on this item at all so I know what is wrong with it. I have taken everything out and have cleaned it and made sure everthing was dry what is wrong with this thing HELP thank you.