Display shows SLP or SL and spa temperature drops significantly between cycles

Safety first: No internal service is needed; this is a configuration issue.

SLP indicates the spa is in Sleep mode, heating only during limited filter cycles and allowing a larger temperature drop.

• Access mode menu: Use the topside control panel to navigate to the mode settings.
• Change to Standard: Select Standard or Ready mode so the heater maintains the set temperature more consistently.
• Adjust set temperature: Confirm the desired set temperature is correctly programmed.
• Allow recovery time: Give the spa several hours to reheat after changing modes, especially in cold weather.

If the spa remains in SLP or does not respond to mode changes, the control panel or board may need service.