Circulation pump is not running; water at heater return is still; spa may show FLO or dr errors

Safety: Turn OFF power at the GFCI breaker before servicing the circulation pump.

• Check for airlock: Loosen the union on the suction side of the circulation pump until water flows steadily, then retighten. Repeat on the discharge side if necessary.
• Inspect for blockages: Check the spa's suction fittings and filter area for debris that could restrict flow to the circulation pump.
• Verify wiring: Ensure the circulation pump plug is fully seated in the correct receptacle on the control pack and that there is no visible damage to the cord.
• Test pump operation: Restore power and observe whether the circulation pump starts during a heating or filtration cycle. If it remains silent and cool to the touch, it may not be receiving power or may be failed.
• Measure voltage (advanced): With power ON and a call for circulation active, measure voltage at the pump terminals. If correct voltage is present but the pump does not run, replace the pump. If no voltage is present, the control board may be at fault.