I have a model #MQC1557AEW free standing freezer. I inherited it and am unsure if it is a frost free. It builds quite a bit of ice around the top gasket and I need to determine if this needs to be replaced or if there is a more serious problem. I tried to find the manual online, but was unable to find one. If you could simply assist me with this question, I would most appreciate it. Thanks so much.