Thread: Blurred PEX labeling

A 1994 home that I inspected with hot water baseboard heat had a new boiler installed. All markings on the PEX tubing were illegible. I have seen this in limited amounts in the past, but never an entire crawl space and mechanical room without a legible label. Does the marking on the tubing have some kind of pressure or heat sensitivity? Could this have occurred due to excessive UV exposure? It appears to be Wirsbo, but I always like to see that appropriate pressure and temperature rating. I've included a picture.

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It's more flexible than polybutylene and opaque. I see quite a bit of PB, that's not it here. Although, you do raise a good question: could someone be trying to hide something?

Originally Posted by Kevin Wood

If it is opaque then they are hiding a low quality line.

So you think that someone deliberately rubbed the words/letters off the pipe to obscure its true origin?

I've seen plenty of pipe (or wire, wood, etc) with blurry markings. Keep looking, you'll find a legible spot somewhere....

Originally Posted by Matt Kozusko

It's more flexible than polybutylene and opaque. I see quite a bit of PB, that's not it here. Although, you do raise a good question: could someone be trying to hide something?

If it is Wirsbo the HePex lettering is black, the AquaPex is blue, if that helps.

Can't help you with identifying this particular PEX but I'd like to point out the importance of having the right PEX installed. It's not generally a temperature or pressure rating that is the issue. PEX designed for a closed loop heating system, such as Wirsbo HEPEX has an oxygen barrier in the material.

If this not a PEX with an oxygen barrier, such as HE PEX it will cause damage to the heating system. PEX used for potable water such as Aquapex will allow oxygen to escape from the contained water causing the heat loop filled with oxygen deprived water which with eat away at the metal surfaces of the system - baseboards, pumps, etc.

Here in Vegas it's a known fact that Wirsbo, if left laying out in the sun the lettering will fade

Originally Posted by Jerry DiGiovanni

Here in Vegas it's a known fact that Wirsbo, if left laying out in the sun the lettering will fade

It is also a known fact that, in Vegas or anywhere else, PEX *is not allowed to be left laying out in the sun* because PEX IS NOT SUNLIGHT RESISTANT and is not to be stored where it is exposed to sunlight.