Heater will not start at all; display is blank and no lights are on

Safety first: Turn OFF the breaker before opening the electrical compartment.

• Check breaker: Locate the dedicated breaker for the Poolworld heater and reset it if tripped. If it trips again immediately, there is likely a short circuit.
• Inspect power connections: Remove the heater's electrical access cover and verify that line wires are securely attached to the terminal block and show no signs of overheating.
• Check internal fuse: Many Poolworld heaters have an internal low-voltage fuse on the control board. With power OFF, inspect and replace with the same type and rating if blown.
• Test power switch: If equipped, ensure the on/off switch is in the ON position and functioning.

Warning: If you are not comfortable working with line voltage, contact a licensed electrician.