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Question

Hello,

 

   I cecently optained an oven after my aunt passed away, with oua a manual. Before bringing it home we pluged it in and it worked fine. About 3 days of using it. It did this> we set the timer for heating and it would shut down after 3 secounds. I pulled the plug and pluged it in again and it worked fine for the dinner. The next morning it did it again after 3 secounds, stopped working.