Question by altechworks: Solar water heater Tank is leaking. How can I seal it?
It has a small leak in the seam. I wish to seal it. What can I use and how should I prep it. Just as temporary solution until I can buy a new tank proper.

Best answer:

Answer by Peetr Peetr
Nobody is ever successful sealing water heater tanks, that’s why you don’t see people doing it all the time.
It’s just a water heater, go buy one before the flood.
And if you mean that it’s just leaking at the outer metal seam, then here’s a news flash, there’s an inner tank, and that’s the one that’s leaking. Plugging the outer seam will do absolutely nothing except send the water up and out another hole or seam.
There’s a super slight chance that the leak is at the top where the pipes attach, and that the water is just dribbling down to the bottom, but I doubt it. Most likely is that the inner tank has finally rotted through in some spot.

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