Display shows HFL and spa may shut down heater; often accompanied by intermittent OH codes.

Safety: Turn off power before working on plumbing.

• Clean filter thoroughly: Remove the Jacuzzi filter cartridge and soak in a filter cleaner solution if heavily soiled. Rinse well.
• Check valves: Verify that all slice valves in the equipment bay are fully open and that any service valves are not partially closed.
• Inspect hoses: Look for kinks or collapsed flex hose on the circulation line to and from the heater.
• Descale heater (advanced): If you have hard water and visible scale, a technician can remove and descale or replace the heater assembly.

If HFL persists after restoring proper flow, the circulation pump may be failing and should be tested for amperage draw and replaced if weak.