Bradford White Water Heater Error Code 0

Error code 0 on a Bradford White water heater indicates that the gas control valve is receiving no electrical power. The control LED, which normally illuminates or flashes to indicate operational status, will be completely dark. This is a fundamental power supply issue rather than a component failure within the gas valve or burner assembly itself. The gas control on these units relies on a continuous low-voltage supply to operate its internal electronics, maintain setpoint logic, and manage ignition sequencing.

The most common entry point for diagnosis is confirming that the unit is physically connected to a live power source. The control power switch on the unit must be in the ON position, and the 120V supply circuit feeding the water heater must be active and uninterrupted. A tripped circuit breaker, a blown fuse on the control board, a loose wiring connection at the power inlet, or a failed transformer that steps voltage down to the control circuit can all result in this condition. Wiring harness integrity between the power supply and the gas control valve should also be inspected for damage, corrosion, or disconnected terminals.

Because this code reflects a complete absence of power rather than a measured fault condition, it does not require interpreting sensor data or resistance readings. The diagnostic path is straightforward: restore power to the gas control and verify the LED activates. If supply voltage is confirmed at the inlet but the control LED remains off, the gas control valve assembly or the internal wiring harness may need closer inspection or replacement.