Heater will not ignite; display shows SPF1 shortly after call for heat

Safety first: Turn off power at the breaker and shut off the gas supply to the SmartPool heater before opening any panels. Allow the heater to cool completely.

• Access the burner compartment: Remove the front service panel of the SmartPool heater to expose the burner tray and flame sensor assembly.
• Locate the flame sensor: Find the thin metal rod (flame sensor) mounted near the main burner. It will have a single insulated wire leading back to the SmartPool ignition control board.
• Clean the sensor: Gently remove the flame sensor using a nut driver. Lightly scrub the metal rod with fine steel wool or a Scotch-Brite pad to remove oxidation and soot. Do not sand aggressively or bend the rod.
• Inspect wiring: Check the flame sensor wire and connector for corrosion, loose fit, or damage. Reseat the connector firmly on the SmartPool control board terminal.
• Reinstall and test: Reinstall the flame sensor, restore gas and power, and call for heat. Observe ignition. If SPF1 returns, the flame sensor or ignition control board may need replacement.
• When to stop: If you smell gas, see delayed ignition (small explosion), or flames roll out of the heater, shut it down immediately and contact a qualified pool heater technician.