John Wood electronic gas water heater shows E007 and will not operate after a power surge or outage

Safety: Disconnect power before accessing the control compartment.

• 1. Hard reset: Turn off power at the breaker for at least 5 minutes. Restore power and see if the code clears.
• 2. Inspect wiring harness: Remove the control cover and check all multi-pin connectors between the display, gas valve, sensors, and main board. Reseat each connector firmly.
• 3. Look for board damage: Examine the control board for burn marks, swollen capacitors, or corrosion. Any visible damage indicates the board should be replaced.
• 4. Surge protection: After replacing a failed board, consider installing a surge protector on the heater's electrical circuit to prevent future damage.
• 5. Firmware issues: If the manufacturer indicates E007 is a firmware-related fault, board replacement is typically the only remedy and must match the exact John Wood model and gas type.