Gas DHW heater plumbed backwards

While installing some pipe insulation, I noticed that the water heater seems to be plumbed in backwards, i.e. the cold supply goes in the union marked "hot" on the casing, and hot exits from the "cold" union.
I do get hot water, almost normally, however when taking a shower (after shave & teeth etc), the water runs hot at first, then cold for a while, before getting hot again. This often puzzled me, but now I suspect this incorrect plumbing may be the cause.
I suspect the difference between the two ports (Hot & Cold) is only that the cold has a "dip tube" internally, so that incoming cold water is directed to the bottom of the tank, and does not immediately mix with the already hot water. Is this so? If it is, how does any really hot water get out?
This is in a condo built about 20 years ago, I don't know if it's the original heater but I guess I could ask the neighbours what they have, and compare brands.
I'm renting this condo for a year, since last August, so I'd need to persuade the owner to get it fixed if it really needs fixing.
Comments?
Another clue they weren't too smart: the furnace takes a 16" x 25" filter, but there's only 23" clearance to the wall, making it very difficult to change.
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John W Hall < snipped-for-privacy@telus.net>
Cochrane, Alberta, Canada.
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There is a possibility that the dip tube was switched over to the Hot side. The only way to tell for sure would be to pull it out.
Dean

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On Sun, 07 Dec 2003 22:21:40 GMT, "Lori & Dean Wigmore"

That thought occurred to me this morning, and I've been wondering if that's possible. Looking at some part pictures on the web, it could be. If so, it may have been done to make the water & gas piping more convenient. But the plumber should have stuck a label there to indicate that.
--
John W Hall < snipped-for-privacy@telus.net>
Cochrane, Alberta, Canada.
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your'e just high, its hooked up fine.

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