I am trying to replace the dip tube in my RheemPowerVent water heater but I can't for the life of me figure out how to get the old one out. The treaded metal cold water nipple is screwed into a circular plate so I assume this circular plate is part of the take and does not come off. The nipple does not have a hex section so I can't put a socket on it. The only thing I can see using is a pipe wrench but that will mess up the threads which is viable as it appears the new tube has a threaded nipple on it provide I have the correct tube.

Well you will need to use a pipe wrench and yes it will mess up the nipple. You will need to buy a new nipple and install it after the tube has been replaced. If you have can get a inside the pipe nipple extractor tool you can remove it (most of the time) unharmed.
It sounds like you a replacement tube that comes with nipple built in, if that the case your good to go without a new nipple.

1) Rheem power vent series:
http://www.rheem.com/product.aspx?id=C24E3F52-A6A4-4BC7-AF5B-0DF23A7A0263

2) Looking at product over-view manual: It says 'inlet connects directly to a dip tube which directs water to bottom of the tank.'
So it appears that dip tub is connected to heat trap nipple on cold water side

3) Sample manual for Rheem shows exploded parts list
http://globalimageserver.com/fetchDocument.aspx?id=a92c7d0e-8a95-48ba-8810-cd714f33d47a
The exploded view shows cold water nipple separate from dip tube, and shows dip tube gasket, and makes it unclear

4) Manual shows Rheem phone number:
1-800-432-8373

5) You can also post specific questions like this on pro water heater forum: http://www.thetankatwaterheaterrescue.com/forums/forum3/

Add a comment for more free help.
Also take advantage of fixya phone service.
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