Water heaters are a huge field of knowledge. Problem is not 100% clear.
There is a resettable thermal switch on the combustion door. This switch is round and has two wires that come from gas control valve. Thermal switch trips when combustion parts have not been cleaned and they cause overheated condition, or sensor reads temperatures above 180, or thermal switch has gone bad, or gas control has gone bad.http://waterheatertimer.org/images/Whirlpool-Resettable-ECO-8.jpg
Add a comment with more information for continued help.
1) Bradford White support:http://www.bradfordwhite.com/supportserv.asp
2) Bradford white mi403s6fbn is 6-year-warranty 40 gallon tank-type gas water heater with Icon electronic gas valve, and atmospheric venting.
Older models have the dial-type Robert Shaw or White Rodgers gas valve.
Open following link to see age of Bradford White:
3) Bradford white has 'product manuals' and 'service manuals' on following link:
Product manuals have general information and advisories that people can read about water heaters.
Service manuals are for plumbers and technicians, and do-it-yourselfers for testing and repairing water heaters.http://www.bradfordwhite.com/documentation/residential/gas.asp
4) Typical manual for your product shows different gas valves, lighting instructions, and advisories, and troubleshoot checklist:http://www.bradfordwhite.com/images/shared/pdfs/manuals/238-44219-00J.pdf
5) Add a comment with following information if you want specific help with servicing water heater.
What are you trying to reset on the water heater?
What are the symptoms, and what have you noticed, and what have you tried so far?
Which gas valve does your water heater have? Please open typical manual and view images of the three basic gas valves.
When was water heater last serviced and cleaned?
How old is water heater?
Take a moment and rate answer:
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