Bradford White Water Heater Error Code 6-4 flash

The 6-4 flash code means the control system detected a pilot flame signal when no flame was supposed to be present, indicating the pilot valve is stuck open. The system identifies this as an out-of-sequence flame condition and logs it as a fault. Bradford White water heaters with this code will attempt an automatic reset, but the gas control valve typically needs to be replaced to resolve the root cause.

A stuck-open pilot valve means gas is flowing to the pilot burner without authorization from the control board, which is an abnormal operating condition. While the heater's auto-reset function will attempt to manage the situation, a pilot valve that cannot close on command is a gas control failure that should be addressed promptly. Do not ignore this fault code or attempt to bypass the control system.

The repair requires replacing the gas control valve assembly, and total costs including parts and labor typically range from around $200 to $500 depending on the specific model, part availability, and local labor rates. If the water heater is older or still under warranty, it is worth checking warranty coverage on the gas control valve before purchasing a replacement.

The fix for this error code is replacement of the gas control valve assembly, which involves disconnecting gas lines and working directly with gas supply components. While a knowledgeable DIYer may be capable of this repair, it is generally recommended that a licensed plumber or gas appliance technician perform the work to ensure safe installation and proper leak testing.

The Bradford White system is designed to auto-reset after detecting this fault, so the heater may resume operation temporarily on its own. However, resetting does not repair the stuck pilot valve that causes the error. The fault is likely to return and the gas control valve will need to be replaced to permanently resolve the condition.