Many problems

We bought a free standing oven in April of 2010 model number GLEFM385DS. We have had nothing but problems. We use the oven twice a week in a special needs classroom to back muffins to sell to help our students raise money for field trips. Appliance retailer has been very difficult for us to work with, resisting our requests for service. They have been out to our building at least 6 times and replaced parts. Each time the problem appears to get worse. We feel the best solution is to replace the unit. They refuse. They have told us that the warranty does not apply because we are a commercial setting. I don't feel it is used in a commercial setting.
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