Hot Water Heater Blues

[SgtRock63]

We have a 2009 Jayco Travel trailer, in 2015, had to replace the hot water heater. The tank had split at the top rear. I was certain I had performed all the winterizing tasks as I normally did in the past, However, be it as it may, replaced it with another Atwood unit. Because I had drained the tank and placed the plug back in, perhaps it was the cause, but knowing how much water would be needed to cause this to split, I doubted it. So, replaced it, and now this last weekend, found it split again, I am baffled by what could cause this, this even has friends of mine that work with metals baffled.

And yes, it was drained, I know this as I forgot the drain was open when filling the tank and had to go out and close it.

Anyone else have this issue? Any ideas?

[stateboy]

Two very remote possibilities...

1) It that water line in your picture lining up well enough to attach smoothly to the tank? If not, is there enough stress that vibration travelling down the road could have caused the crack?

2) Is it possible that you may have left the water heater on without water in it?

I know these are far fetched since it sounds like the unit was in storage when it occurred but I just want to make sure I read your post correctly.

[vcbice]

Without being there it looks like the section of metal along the crack was heated. And the joint of pipe fitting to metal looks like there is a flaw as well.

The alignment could be an issue and twisting of fitting when installing the pipe might be an issue as well.

[ALJO]

Have it welded for a couple of hundred dollars, versus 1200 for a new one.