Shop replacement repair parts for Bradford White Water Heater model MI403S6EN12

Pilot assy / nat / w/t-couple / white rod e63n-715

Gas valve LP

Natural gas control valve
Maintain consistent hot water delivery from your Bradford White MI403S6EN12 gas water heater with genuine OEM replacement parts from Repair Clinic. The MI403S6EN12 is a 40-gallon atmospheric vented gas water heater in Bradford White’s energy-efficient residential line. The anode rod is a sacrificial component that corrodes preferentially to protect the steel tank from rust; replacing the anode rod every two to five years, depending on local water hardness, extends tank life significantly and is one of the most overlooked preventive maintenance items on gas water heaters. Parts most frequently replaced include the thermocouple, pilot assembly, gas control valve, anode rod, and drain valve. Use the MI403S6EN12 parts list and browse the full Bradford White water heater parts catalog.
The Bradford White MI403S6EN12 is a 40-gallon atmospheric vented gas water heater designed for residential use. The anode rod, often overlooked during routine service, is a magnesium or aluminum rod that corrodes in place of the steel tank through galvanic action; checking and replacing this rod every two to five years (depending on local water hardness) is one of the most cost-effective preventive maintenance steps available, since a fully consumed anode rod leaves the tank itself vulnerable to corrosion and eventual leaking. The related M4403T6EN12 shares many components with the MI403S6EN12; always verify part compatibility using the product’s model number or by reaching out to support before cross-ordering between these designations. For repair guidance, visit the Bradford White water heater repair help section.
Inspect the MI403S6EN12 anode rod every two to five years depending on local water hardness; harder water accelerates anode consumption. A rod that has been reduced to a thin core wire, or that shows the steel core wire exposed along significant lengths, requires replacement to continue protecting the tank from corrosion. This single maintenance step is frequently skipped but significantly extends water heater service life.
Start by checking the pilot light, thermocouple, and gas valve when troubleshooting ignition failure. A pilot light that will not stay lit most commonly has a failed thermocouple that cannot maintain the gas valve’s safety circuit signal; replace the thermocouple before assuming a gas valve fault.
For no hot water or inconsistent temperature, inspect the thermostat and burner assembly. A burner that produces a weak or uneven flame pattern reduces heating efficiency even when the thermostat and gas valve are functioning correctly.
Some parts may be shared between the M4403T6EN12 and MI403S6EN12 models. Use the model number and part diagrams to confirm compatibility before purchase, since these closely related designations may have differing tank capacities or burner specifications.
The MI403S6EN12 is a 40-gallon gas water heater designed for residential use, part of Bradford White’s energy-efficient, atmospheric vented series. It uses a standard gas burner and pilot assembly with a thermocouple safety circuit.
Inspect and replace the anode rod every two to five years depending on local water hardness; harder water accelerates anode consumption and shortens the inspection interval needed. This frequently overlooked maintenance step protects the steel tank from corrosion and significantly extends the water heater’s overall service life.
Some parts may be shared between the M4403T6EN12 and MI403S6EN12 models. Use the model number and part diagrams to confirm compatibility before purchase, since tank capacity or burner specifications may differ between these closely related designations.
Start by checking the pilot light, thermocouple, and gas valve for ignition issues. For no hot water or inconsistent temperature, inspect the thermostat and burner assembly. A pilot that won’t stay lit most commonly indicates thermocouple failure rather than a gas valve problem.

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