Yesterday I lit my stove for the first time this year and I have smoke leaking out the back. I think a gasket may be the problem, but I am not sure. Any suggestions? If it is the gasket, do I have to call a pro? Can I take the back off to find the gasket? Is this a costly issue? The stove is only a few years old, but the place I where I purchased it was terrible with customer service and I don't think they will be eager to help me. Please help me!