Problems with my AO SMith

Old 07-23-12, 05:57 PM
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Problems with my AO SMith

Hi I need HELP my AO SMITH 120 vac GPSH40200 40 gallons, B06a000342 120 volts, keeps shutting off. The ceramic ignitor lits up, I see flames come on and right after that the fan shuts off and the flames goes off...I need to reset it t least 10 times before it stays on.... I have tried to clean it, vacunned it and still nothing.. Please help
Old 07-23-12, 07:07 PM
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I moved your post to its own thread.

I would say off the top of my head its the flame sensor. This is part of the hot surface igniter and comes as an assembly.

Looks like you are 5 months out of warranty. But I will check. It does depend when the unit was installed though and the date is simply when the heater was manufactured.
Old 07-24-12, 08:17 PM
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Hope this helps, he said it so much better then I could:
copied from:

Eventually it will fail and I can say with 95% certainty it's a dirty flame sensor. Unplug the water heater, remove the door at the bottom and then take out all of the screws around that observation window and the gas inlet pipe, on mine it was 7 screws. Now pull out the burner, attached is the igniter and flame sensor. On this pic, the flame sensor is the metal rod on the right:

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Get a piece of 60 grit sand paper and sand until it's nice and shiny, especially the tip. Reverse the process and plug it back in. Wait 1 hour and enjoy a nice hot shower!

It's a piece of maintenence that most water heaters and furnaces need occasionally, like brake pads on a car, nobody expects them to last forever.

BTW, it might be a nice service reminder that if you need to clean it every 5 years, to also replace the annode rod at the same time and drain the tank to clear out any sediment, it will increase the life of your water heater significantly!

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