If the water temperature is cold remove your saltwater system from the water and keep in a safe place until you will use the spa again. Chlorine generators do not operate efficiently or at all at low temperatures and this may degrade the life span of the titanium plates.
Do not operate the chlorine generators power supply when the outside temperature is below freezing. In freezing weather make sure to put the power supply in a safe place until the weather warms above freezing. The power supply may not survive if operated at very low temperatures.
We have had some power supplies fail while operating at temperatures below freezing. If you must do that locate the supply in with the spa equipment to keep it warmer. We will be offering a lower operating temperature power supply in the near future.