Control panel shows HL and spa stops heating; pumps may still run in low speed.

Safety: Turn off power at the breaker before touching plumbing or electrical components.

• Verify water level: Make sure the spa is filled to the recommended level on the MAAX shell skimmer mark.
• Remove and clean filters: Take out all MAAX filter cartridges and hose them off thoroughly. Try running the spa without filters to see if HL clears after a power cycle.
• Bleed air from heater: With power off, slightly loosen the union fittings on the heater tube until water flows steadily, then retighten. This removes trapped air that can cause dry-fire.
• Check circulation pump operation: Restore power and observe the small circulation jet. If there is no flow, the MAAX circulation pump may be seized or air-locked. Gently tap the pump housing and restart; if still no flow, the pump likely needs replacement.
• Reset system: Turn power off for 5 minutes, then back on. If HL returns quickly with good flow and clean filters, the high-limit sensor or control board may be defective and should be tested by a technician.