Thermopile Low Voltage, after replacing thermopile

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Bill0226

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Honeywell WV8840B1042 gas valve; Whirlpool N40T61-343 water heater

Heater went cold, and controller indicated the two flashes for Thermopile Low Voltage.
After replacing thermopile which included the igniter and gas supply pipe, the pilot goes out immediately after releasing control knob. I get the same code two-flash code as before, Thermopile Low Voltage. However, checking thermopile leads with pilot on, I get 820 mvdc, i.e. within normal range. There are no drafts and air intakes are clean.
Why do I continue getting the same code, with a functioning thermopile?
 

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Twowaxhack

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The control or the connection to the control is bad.

You tested the output so that’s the only thing left.

I’ll say it again as I’ve said it many times, that’s the worst control ever made snd it should be removed from the market IMO
 

Bill0226

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The control or the connection to the control is bad.

You tested the output so that’s the only thing left.

I’ll say it again as I’ve said it many times, that’s the worst control ever made snd it should be removed from the market IMO
Installed new gas control valve ($125) and VOILA! HOT WATER! THANKS FOR ADVICE!

Old thermopile was probably fine, but never occurred to me to check voltage before I replaced it - I assumed the controller was telling the truth! Now I know better. But then if I hadn’t replaced thermopile, I wouldn’t have known about the cracked burner assembly. All new down below now. Drain water looked very clean, so I’m guessing tank is in good shape. Good to go! Thanks again!
 
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