On Mon, 09 Apr 2007 18:14:39 +0100,
wrote:

|!Sorry if this has been asked before but...
|!
|!Why are all domestic hot water cylinders made of copper/stainless steel?
|!Don't we have any plastic (e.g. PEX) ones?
|!
|!Also, are they any shape other than cylindrical?
|!
|!I'm researching an essay for college and any insight will be
|!appreciated!

Research the strength of plastics at hot water temperature, say 90 deg C,
as compared with copper.

Research the strength of various shapes when under internal pressure.
--
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