I purchased a home with radiant floor heat (which was installed about 15 yrs ago). What seems odd to me is that I have copper pipes coming out of the concrete. (I was anticipating PEX or similar). Is the copper I see just a termination, with a copper to PEX connection buried in the concrete, or is it possible (or even probable) that the whole system is copper? Pleading ignorance here, so any input would be greatly appreciated. Thanks and Regards, Larry S.