Bradford White Water Heater Error Code 4 flashes (V1)

The 4-flash error code on a Bradford White water heater with a V1 gas control indicates that the unit has detected an excessive tank temperature condition. This is a safety-triggered lockout designed to prevent overheating, scalding, or tank damage. The heater will shut down and require a manual reset before it can resume normal operation. The V1 gas control valve integrates the thermostat, temperature sensing, and gas regulation functions into a single assembly, which means faults in any of those sub-functions can trigger this code.

Two primary causes drive this fault. First, the temperature sensor embedded in or connected to the gas control may drift out of calibration or fail outright, causing the unit to read falsely elevated temperatures even when the actual tank temperature is within normal range. Second, the gas control itself may be malfunctioning, allowing the burner to fire beyond the setpoint and genuinely overheating the tank. Distinguishing between a false reading and an actual overheat condition is critical before resetting, as returning a true overheat situation to service without addressing the root cause poses a safety risk.

Because the temperature sensor and gas control are not serviceable as separate components on the V1 platform, the diagnostic path leads directly to gas control replacement. Before replacing the unit, technicians should verify that the reset procedure is performed correctly, check for any signs of actual overheating such as relief valve discharge or discolored flue components, and confirm that the tank has cooled to a safe operating temperature. If the fault returns promptly after reset and replacement of the gas control, inspect for external causes such as cross-connections or recirculation loop issues driving tank temperature above normal limits.