I have a Bradford white defender gas water heater. To drain 1 gallon of water monthly do I have to disconnect or do anything else other than attach hose and drain?

It is pretty easy - make sure gas valve is open, change control know to pilot. Press the ignitor a few times and once pilot lights up switch control to warm or hot position.

See instructions by downloading manual for MI-403SF6BN from this site
Bradford White Water Heaters Built to be the best

http://waterheatertimer.org/How-to-fix-water-heater.html

What type water heater? gas or electric, tank or tankless?
Gene
h

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Usually 1 minute.
Copy following link to identify gas control valve and read lighting instructions:
http://waterheatertimer.org/How-to-light-gas-water-heater.html

Gene
h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

Call Bradford White or installer

Gene
h

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

1) Do you mean NG natural gas to propane?

2) Most companies do not support gas-type conversion, especially with modern FVIR-compliant heaters. New burner, gas control are required at minimum.

3) Contact Bradford White and include model number, serial number that appear on label on side of unit.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

1) Copy following links to identify gas control valve and read ignition procedure, and access service manual for your product:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

2) Honeywell gas control used on recent Bradford White gas water heaters has red knob that rotates to pilot. Press and hold red knob. Then push red igniter button until status light changes.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

1) Just open the following link to identify gas control, and following instructions for lighting each gas control that appear under the gas control that looks like yours.
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

2) Otherwise add a comment and carefully describe gas control valve, and then open link and compare your description to pictures of each gas control valve, and then look below each picture for link that says how to light water heater.

3) Call plumber.or local service technician, or local BW supplier who can recommend technician.

4) Call Bradford White to get recommendation of local technician.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Doesn't sound like its the dip tube, its a element problem, I would contact bw directly to see if heater is stil in warranty and they will send you new parts free.

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:
http://www.bradfordwhite.com/findaserial.asp

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?

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