Difficulty with VWR Symphony water jacketed CO2 incubator

We are getting alot of condensation inside the unit, wondering if its time to replace the temperature prob? We noticed a few years ago that the temperature reading on the digital display screen DOES NOT match what we are getting on the reference thermometer inside the incubator The unit has not had that much usage (used during Jan-April for cell culutr lab course every year) but its been giving us problems over the last few years. Any help would be greatly appreciated.

BTW the CO2 levels are stable and no problems with respect to 5% CO2 with the incubator.