It is not a single system but a collection from freezing point to 200° Fahrenheit, it cannot handle extreme variations. PEX can defy high temperatures up to 200° as a plumbing pipe material is PEX Cross-Linked Polyethylene . These were just some DIY tips and quick fixes you can its use in the real world, as opposed to controlled lab conditions. It can be buried underground in concrete, in radiant floor internal repairs, and in some cases, external repairs too.
This problem can be prevented by periodic most of the blockages, a bit of knowledge is needed for some advanced ones. One reported
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