Display shows COL and spa enters a cool or protection mode; heating may be limited.

Safety first: Ensure all pumps and heater are protected from freezing conditions.

• Verify actual water temperature:
  • Use an external thermometer to confirm water temperature.
• Allow spa to warm:
  • If spa was just refilled with cold water, allow time for gradual heating.
• Check sensor accuracy:
  • If display shows much colder than actual, inspect and test the temperature sensor.
  • Replace sensor if readings are inaccurate.
• Ensure circulation:
  • Confirm that circulation pump runs during freeze protection to prevent damage.