I have a Hayward Swim Pure Plus T-CELL-9 SWG that is almost a year old. Up until November I was getting a flashing indicator to inspect the cell on a regular basis, approx every 3 months. According to the manual the reminder/flashing indicator will occur after approx 500 hours of operation. The flashing indicator hasn't come on since about November. And of this date, I know for sure the pump has been running more than 1000 hours. Other than that, the unit is producing chlorine and seems to be working fine. Any ideas? Is a service call recommended? Unit is still under warranty.