This morning the temperature dropped into the 30's and this message popped up on my aqualogic display unit. A few weeks back I got the "no cell power" message and I got that taken care of. At first I didn't think anything of the message because when its cold outside you get funny readings sometimes but my check system light had stayed on all day. It is telling me to check the cell and hold the + sign to reset it. What is happening to cause this issue?