This is a question more for anybody who knows a lot about the workings of chest freezers. My keezer has been humming along for almost 2 years now on a Johnson 419 controller. Lately the temperature has been stuck at 41deg. I noticed an ice buildup on the front wall of the freezer and thought this might have something to do with the problem. I unplugged the freezer and let the ice melt so it fell off then started it up again. Now I'm getting ice buildup in the same spot again but the temp is down to 38deg, but the Johnson controller is always commanding the freezer to be on. I have a fan inside circulating air and I have the tower cooled with a blower box. Is the ice formation what's responsible for this problem?