Hot Water Tanks Strange Corrosion

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tk44189

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Can someone please take a look at these pictures and tell me what the heck is going on here and if its something to be concerned with. Sorry for the one blurry pic.

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It appears to be dielectric corrosion, possibly due to non-PEX lined nipples (the unions appears to be dialectic).

The corrosion appears to have spread under the WH top lid to surface around the flue opening. The TPRV/tank fitting connection is also corroded.

Maybe better check the water pH for acidity. Do you have a water softener in the system?
 
I disagree. If it was a dielectric corrosion problem, it would be really bad at the union connections. Understanding a pic is as good as we got, it looks like the tank has been leaking from the inside, based on the small amount of stuff coming from the seam above the decal on the tank. Something is definitely wrong and would shut down that tank immediately until you determine exactly what is happening.
 
Not di-electric problem. Water heater is kaput, worn out, shot, rusted through. Replace ASAP before the corrosion progresses to a catastrophic failure and results in an expensive flood.
 
Those dielectric unions look brand new. I'm guessing they didn't have them, they failed and saturated the fiberglass. THEN, someone replaced the unions and put it back in service?
 
Those dielectric unions look brand new. I'm guessing they didn't have them, they failed and saturated the fiberglass. THEN, someone replaced the unions and put it back in service?

They look (to me) as showing calcium rich leakage @ the unions. The actual failure would occur @ the nipples first as opposed to the unions (their corrosion breakdown would happen inside before complete failure).

It would be interesting to inspect the anode rod, pH and hardness in the system.

Am I on the right track? :confused:
 
OP's water heater looks like many, many typical rusted out water heaters. Nothing strange about the appearance, just few people have seen even one water heater wear out. Strangely, it has been my experience dielectric unions cause water heater premature failure, NOT prevent it. I do not use them anymore and have had much better results.
 
OP's water heater looks like many, many typical rusted out water heaters. Nothing strange about the appearance, just few people have seen even one water heater wear out.

Strangely, it has been my experience dielectric unions cause water heater premature failure, NOT prevent it. I do not use them anymore and have had much better results.

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I have always been told never to mix galvinized with copper. Even at different parts of a water system due to the galvinized partials transferring through the system and eating at the copper. Has anyone else seen this or heard of it. I'm always up for correction or reproof if I can learn from it.
 
I have always been told never to mix galvinized with copper. Even at different parts of a water system due to the galvinized partials transferring through the system and eating at the copper. Has anyone else seen this or heard of it. I'm always up for correction or reproof if I can learn from it.


yes sir, it is called electrolysis

dis similar metals,

i use brass nipples on my water heaters

do not have any problems,

>>>>routine maintenance>>>>

remove the fittings, clean the rust up with a 1'' copper cleaning brush
{attached to drill]

inspect the threads, replumb and be done with it

if the threads are serviceable their is no earthly reason to throw the heater out
 
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New water heaters come with dielectric nappies should not need dielectric unions should not need to switch out nipples
 
i use brass nipples on my water heaters

do not have any problems,

We used to install heaters that came without preinstalled nipples and we always used brass nipples and the a copper flex connector.

I have seen more nipple connection failures with the dielectric unions on galv steel nipples than I have with brass nipples.

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me also, i have gone back to doing everything old school, piss on the "new" stuff

what i have seen work for 30 years is what i do.

i even,, put a tee in a vent line, about 7' off the floor with a 2'' ptrap for ac drains

piss on running 40' of pvc that backs up every year do to algee

flood.jpg
 
Looks to me like chronic backdrafting of the flue gases, combined with poor combustion. It appears to be soot on the top of the heater, coming out from under the hood. See the legs of the draft diverter? The soot is stopped by the legs. The flue gases of gas combustion are about 9% water vapor, which contributes to corrosion.
This could also be a CO problem.
 

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