Jacuzzi pool heater shows F8 and will not fire; may occur immediately on power-up.

Critical safety warning: A rollout fault indicates flames or excessive heat leaving the combustion chamber. Turn off power and gas immediately. Do not reset and operate the heater until the cause is found and corrected.

Steps (for inspection only):

• Locate rollout switch: Find the manual reset rollout switch near the burner compartment. If the button is popped, it has tripped due to excessive heat.
• Inspect burner area: Look for soot, discoloration, or melted wiring around the burners—signs of improper combustion or blockage.
• Check for obstructions: Inspect the burner tray and heat exchanger inlet for debris, rust flakes, or insect nests. Do not attempt deep cleaning without proper training.
• Do not bypass safety devices: Never jumper or bypass the rollout switch. If it has tripped, a combustion problem exists that must be corrected.

Contact a licensed gas technician or Jacuzzi-authorized service provider to clean the burners, verify gas pressure, inspect the heat exchanger, and reset/replace the rollout switch as needed.