I purchased my new Behmor in Feb from SM. I struggled thru several roasts without success. Most being under roasted. I contacted Behmor service and reported my results. The tech determined that two thermisters may be defective and immediately sent two replacement parts with detailed instructions for the repair. I installed the parts and roasted two batches to perfection. I must also say, that, along with the replacement parts, they sent some complementary green beans, and great roasting hints. THANK YOU.